From 8f7f6aa92084cec5b2453e26185547dc82b8ebbc Mon Sep 17 00:00:00 2001
From: Robert von Burg <eitch@eitchnet.ch>
Date: Fri, 3 Jul 2015 15:11:49 +0200
Subject: [PATCH] [Major] Major refactoring of toDom and toSax implementations
 - adding Activity and Action - remove methods on model itself and move to
 visitors

---
 ch.eitchnet.utils                             |   2 +-
 .../strolch/model/AbstractStrolchElement.java |  28 --
 .../model/GroupedParameterizedElement.java    |  30 --
 .../li/strolch/model/ModelStatistics.java     |  11 +
 .../src/main/java/li/strolch/model/Order.java |  43 +-
 .../java/li/strolch/model/ParameterBag.java   |  22 --
 .../strolch/model/ParameterizedElement.java   |  85 ----
 .../main/java/li/strolch/model/Resource.java  |  65 +--
 .../java/li/strolch/model/StrolchElement.java |  14 -
 .../li/strolch/model/StrolchValueType.java    | 374 ++++++++++++++++++
 .../src/main/java/li/strolch/model/Tags.java  |   6 +-
 .../li/strolch/model/activity/Action.java     |  84 ++--
 .../li/strolch/model/activity/Activity.java   |  71 ++--
 .../model/activity/IActivityElement.java      |  12 +-
 .../model/parameter/AbstractParameter.java    |  73 ----
 .../model/parameter/BooleanParameter.java     |  33 +-
 .../model/parameter/DateParameter.java        |  33 +-
 .../model/parameter/DurationParameter.java    |  34 +-
 .../model/parameter/FloatListParameter.java   |  32 +-
 .../model/parameter/FloatParameter.java       |  34 +-
 .../model/parameter/IntegerListParameter.java |  32 +-
 .../model/parameter/IntegerParameter.java     |  34 +-
 .../model/parameter/LongListParameter.java    |  32 +-
 .../model/parameter/LongParameter.java        |  34 +-
 .../li/strolch/model/parameter/Parameter.java |  12 +-
 .../model/parameter/StringListParameter.java  |  32 +-
 .../model/parameter/StringParameter.java      |  34 +-
 .../timedstate/AbstractStrolchTimedState.java |  74 ----
 .../model/timedstate/BooleanTimedState.java   |  51 +--
 .../model/timedstate/FloatTimedState.java     |  51 +--
 .../model/timedstate/IntegerTimedState.java   |  51 +--
 .../model/timedstate/StringSetTimedState.java |  73 +---
 .../model/timedstate/StrolchTimedState.java   |  10 +
 .../li/strolch/model/timevalue/IValue.java    |   5 +
 .../strolch/model/timevalue/IValueChange.java |  35 +-
 .../model/timevalue/impl/BooleanValue.java    |   6 +
 .../model/timevalue/impl/FloatValue.java      |   6 +
 .../model/timevalue/impl/IntegerValue.java    |   6 +
 .../model/timevalue/impl/StringSetValue.java  |  17 +-
 .../model/timevalue/impl/ValueChange.java     |  29 +-
 .../model/xml/AbstractToSaxWriterVisitor.java | 100 +++--
 .../model/xml/ActivityToDomVisitor.java       |  51 +++
 .../model/xml/ActivityToSaxWriterVisitor.java |  49 +++
 .../model/xml/OrderFromDomVisitor.java        |  58 +++
 .../strolch/model/xml/OrderToDomVisitor.java  |  18 +-
 .../model/xml/OrderToSaxWriterVisitor.java    |   3 +-
 .../model/xml/ResourceFromDomVisitor.java     | 105 +++++
 .../model/xml/ResourceToDomVisitor.java       |  18 +-
 .../model/xml/ResourceToSaxWriterVisitor.java |   3 +-
 .../xml/StrolchElementFromDomVisitor.java     | 122 ++++++
 .../model/xml/StrolchElementToDomVisitor.java | 222 +++++++++++
 .../model/xml/XmlModelSaxFileReader.java      |   3 +-
 .../strolch/model/xml/XmlModelSaxReader.java  | 224 +++++------
 .../test/java/li/strolch/model/ModelTest.java |   4 +
 .../java/li/strolch/model/XmlToDomTest.java   |   9 +-
 .../li/strolch/model/activity/ActionTest.java |   3 +-
 .../strolch/model/activity/ActivityTest.java  |   3 +-
 .../resources/data/activities/Activities.xml  | 100 ++++-
 .../resources/data/resources/Resources.xml    |   8 +-
 .../li/strolch/command/ClearModelCommand.java |  15 +
 .../command/XmlExportModelCommand.java        |  14 +
 61 files changed, 1605 insertions(+), 1237 deletions(-)
 create mode 100644 li.strolch.model/src/main/java/li/strolch/model/StrolchValueType.java
 create mode 100644 li.strolch.model/src/main/java/li/strolch/model/xml/ActivityToDomVisitor.java
 create mode 100644 li.strolch.model/src/main/java/li/strolch/model/xml/ActivityToSaxWriterVisitor.java
 create mode 100644 li.strolch.model/src/main/java/li/strolch/model/xml/OrderFromDomVisitor.java
 create mode 100644 li.strolch.model/src/main/java/li/strolch/model/xml/ResourceFromDomVisitor.java
 create mode 100644 li.strolch.model/src/main/java/li/strolch/model/xml/StrolchElementFromDomVisitor.java
 create mode 100644 li.strolch.model/src/main/java/li/strolch/model/xml/StrolchElementToDomVisitor.java

diff --git a/ch.eitchnet.utils b/ch.eitchnet.utils
index 1689ff69a..9e449e56e 160000
--- a/ch.eitchnet.utils
+++ b/ch.eitchnet.utils
@@ -1 +1 @@
-Subproject commit 1689ff69a93f7fcf491400e36b941c905d368018
+Subproject commit 9e449e56eedc01ef24b9d4a8a5cbf5c52b013a48
diff --git a/li.strolch.model/src/main/java/li/strolch/model/AbstractStrolchElement.java b/li.strolch.model/src/main/java/li/strolch/model/AbstractStrolchElement.java
index 44783903d..123572a80 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/AbstractStrolchElement.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/AbstractStrolchElement.java
@@ -19,9 +19,6 @@ import java.text.MessageFormat;
 
 import li.strolch.exception.StrolchException;
 import li.strolch.model.Locator.LocatorBuilder;
-
-import org.w3c.dom.Element;
-
 import ch.eitchnet.utils.helper.StringHelper;
 
 /**
@@ -114,31 +111,6 @@ public abstract class AbstractStrolchElement implements StrolchElement {
 		clone.setName(getName());
 	}
 
-	protected void fillElement(Element element) {
-		element.setAttribute(Tags.ID, getId());
-		element.setAttribute(Tags.NAME, getName());
-		element.setAttribute(Tags.TYPE, getType());
-	}
-
-	/**
-	 * Builds the fields of this {@link StrolchElement} from a {@link Element}
-	 *
-	 * @param element
-	 */
-	protected void fromDom(Element element) {
-		String id = element.getAttribute(Tags.ID);
-		String name = element.getAttribute(Tags.NAME);
-
-		if (id != null && name != null) {
-			setId(id);
-			setName(name);
-		} else {
-			String msg = "Check the values of the element: {0} either id or name attribute is null!"; //$NON-NLS-1$
-			msg = MessageFormat.format(msg, element.getNodeName());
-			throw new StrolchException(msg);
-		}
-	}
-
 	@Override
 	public int hashCode() {
 		final int prime = 31;
diff --git a/li.strolch.model/src/main/java/li/strolch/model/GroupedParameterizedElement.java b/li.strolch.model/src/main/java/li/strolch/model/GroupedParameterizedElement.java
index cbb073571..a211bba1e 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/GroupedParameterizedElement.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/GroupedParameterizedElement.java
@@ -25,10 +25,6 @@ import java.util.Set;
 import li.strolch.exception.StrolchException;
 import li.strolch.exception.StrolchModelException;
 import li.strolch.model.parameter.Parameter;
-
-import org.w3c.dom.Element;
-import org.w3c.dom.NodeList;
-
 import ch.eitchnet.utils.helper.StringHelper;
 
 /**
@@ -291,32 +287,6 @@ public abstract class GroupedParameterizedElement extends AbstractStrolchElement
 		return new HashSet<String>(this.parameterBagMap.keySet());
 	}
 
-	@Override
-	public void fromDom(Element element) {
-		super.fromDom(element);
-
-		String type = element.getAttribute(Tags.TYPE);
-		setType(type);
-
-		NodeList bags = element.getElementsByTagName(Tags.PARAMETER_BAG);
-		for (int i = 0; i < bags.getLength(); i++) {
-			Element bagElement = (Element) bags.item(i);
-			ParameterBag bag = new ParameterBag(bagElement);
-			addParameterBag(bag);
-		}
-	}
-
-	@Override
-	protected void fillElement(Element element) {
-		super.fillElement(element);
-
-		if (this.parameterBagMap != null) {
-			for (ParameterBag bag : this.parameterBagMap.values()) {
-				element.appendChild(bag.toDom(element.getOwnerDocument()));
-			}
-		}
-	}
-
 	/**
 	 * Fills {@link GroupedParameterizedElement} properties of this clone
 	 * 
diff --git a/li.strolch.model/src/main/java/li/strolch/model/ModelStatistics.java b/li.strolch.model/src/main/java/li/strolch/model/ModelStatistics.java
index 31a70b0d4..30c21f1fa 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/ModelStatistics.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/ModelStatistics.java
@@ -80,6 +80,17 @@ public class ModelStatistics {
 		return this.nrOfActivities;
 	}
 
+	/**
+	 * Adds the statistics of the other statistics to this statistics instance
+	 * 
+	 * @param statistics
+	 */
+	public void add(ModelStatistics statistics) {
+		this.nrOfOrders += statistics.nrOfOrders;
+		this.nrOfResources += statistics.nrOfResources;
+		this.nrOfActivities += statistics.nrOfActivities;
+	}
+
 	@Override
 	public String toString() {
 		StringBuilder builder = new StringBuilder();
diff --git a/li.strolch.model/src/main/java/li/strolch/model/Order.java b/li.strolch.model/src/main/java/li/strolch/model/Order.java
index fe08fcb9a..b0d4ea9ff 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/Order.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/Order.java
@@ -19,11 +19,6 @@ import java.util.Date;
 
 import li.strolch.model.Locator.LocatorBuilder;
 import li.strolch.model.visitor.StrolchRootElementVisitor;
-
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-
-import ch.eitchnet.utils.helper.StringHelper;
 import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
 
 /**
@@ -80,30 +75,6 @@ public class Order extends GroupedParameterizedElement implements StrolchRootEle
 		setDate(date);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public Order(Element element) {
-		super.fromDom(element);
-
-		String date = element.getAttribute(Tags.DATE);
-		String state = element.getAttribute(Tags.STATE);
-
-		if (StringHelper.isEmpty(date)) {
-			setDate(ISO8601FormatFactory.getInstance().getDateFormat().parse("-")); //$NON-NLS-1$
-		} else {
-			setDate(ISO8601FormatFactory.getInstance().getDateFormat().parse(date));
-		}
-
-		if (state == null || state.isEmpty()) {
-			setState(State.CREATED);
-		} else {
-			setState(State.valueOf(state));
-		}
-	}
-
 	/**
 	 * @return the date
 	 */
@@ -134,18 +105,6 @@ public class Order extends GroupedParameterizedElement implements StrolchRootEle
 		this.state = state;
 	}
 
-	@Override
-	public Element toDom(Document doc) {
-
-		Element orderElement = doc.createElement(Tags.ORDER);
-		fillElement(orderElement);
-
-		orderElement.setAttribute(Tags.DATE, ISO8601FormatFactory.getInstance().formatDate(this.date));
-		orderElement.setAttribute(Tags.STATE, this.state.toString());
-
-		return orderElement;
-	}
-
 	@Override
 	public Order getClone() {
 		Order clone = new Order();
@@ -179,7 +138,7 @@ public class Order extends GroupedParameterizedElement implements StrolchRootEle
 	public Order getRootElement() {
 		return this;
 	}
-	
+
 	@Override
 	public boolean isRootElement() {
 		return true;
diff --git a/li.strolch.model/src/main/java/li/strolch/model/ParameterBag.java b/li.strolch.model/src/main/java/li/strolch/model/ParameterBag.java
index 3d59f23e4..8bc9541a4 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/ParameterBag.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/ParameterBag.java
@@ -17,9 +17,6 @@ package li.strolch.model;
 
 import li.strolch.model.Locator.LocatorBuilder;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  */
@@ -45,15 +42,6 @@ public class ParameterBag extends ParameterizedElement {
 		super(id, name, type);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param bagElement
-	 */
-	public ParameterBag(Element bagElement) {
-		super.fromDom(bagElement);
-	}
-
 	@Override
 	public ParameterBag getClone() {
 		ParameterBag clone = new ParameterBag();
@@ -68,16 +56,6 @@ public class ParameterBag extends ParameterizedElement {
 		lb.append(this.id);
 	}
 
-	@Override
-	public Element toDom(Document doc) {
-
-		Element element = doc.createElement(Tags.PARAMETER_BAG);
-
-		fillElement(element);
-
-		return element;
-	}
-
 	@Override
 	public boolean isRootElement() {
 		return false;
diff --git a/li.strolch.model/src/main/java/li/strolch/model/ParameterizedElement.java b/li.strolch.model/src/main/java/li/strolch/model/ParameterizedElement.java
index 95242e77d..6810dbbcd 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/ParameterizedElement.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/ParameterizedElement.java
@@ -26,23 +26,7 @@ import java.util.Set;
 
 import li.strolch.exception.StrolchException;
 import li.strolch.model.Locator.LocatorBuilder;
-import li.strolch.model.parameter.BooleanParameter;
-import li.strolch.model.parameter.DateParameter;
-import li.strolch.model.parameter.DurationParameter;
-import li.strolch.model.parameter.FloatListParameter;
-import li.strolch.model.parameter.FloatParameter;
-import li.strolch.model.parameter.IntegerListParameter;
-import li.strolch.model.parameter.IntegerParameter;
-import li.strolch.model.parameter.LongListParameter;
-import li.strolch.model.parameter.LongParameter;
 import li.strolch.model.parameter.Parameter;
-import li.strolch.model.parameter.StringListParameter;
-import li.strolch.model.parameter.StringParameter;
-
-import org.w3c.dom.Element;
-import org.w3c.dom.NodeList;
-
-import ch.eitchnet.utils.dbc.DBC;
 import ch.eitchnet.utils.helper.StringHelper;
 
 /**
@@ -206,75 +190,6 @@ public abstract class ParameterizedElement extends AbstractStrolchElement {
 		return lb.build();
 	}
 
-	// TODO remove the whole fromDom methods from strolch model - we want to use the visitor pattern only!
-
-	@Override
-	protected void fromDom(Element element) {
-		super.fromDom(element);
-
-		String type = element.getAttribute(Tags.TYPE);
-		setType(type);
-
-		// add all the parameters
-		NodeList parameterElements = element.getElementsByTagName(Tags.PARAMETER);
-		for (int i = 0; i < parameterElements.getLength(); i++) {
-			Element paramElement = (Element) parameterElements.item(i);
-			String paramtype = paramElement.getAttribute(Tags.TYPE);
-
-			DBC.PRE.assertNotEmpty("Type must be set on Parameter for bag with id " + this.id, paramtype);
-
-			if (paramtype.equals(StringParameter.TYPE)) {
-				StringParameter param = new StringParameter(paramElement);
-				addParameter(param);
-			} else if (paramtype.equals(IntegerParameter.TYPE)) {
-				IntegerParameter param = new IntegerParameter(paramElement);
-				addParameter(param);
-			} else if (paramtype.equals(FloatParameter.TYPE)) {
-				FloatParameter param = new FloatParameter(paramElement);
-				addParameter(param);
-			} else if (paramtype.equals(LongParameter.TYPE)) {
-				LongParameter param = new LongParameter(paramElement);
-				addParameter(param);
-			} else if (paramtype.equals(DateParameter.TYPE)) {
-				DateParameter param = new DateParameter(paramElement);
-				addParameter(param);
-			} else if (paramtype.equals(DurationParameter.TYPE)) {
-				DurationParameter param = new DurationParameter(paramElement);
-				addParameter(param);
-			} else if (paramtype.equals(BooleanParameter.TYPE)) {
-				BooleanParameter param = new BooleanParameter(paramElement);
-				addParameter(param);
-			} else if (paramtype.equals(StringListParameter.TYPE)) {
-				StringListParameter param = new StringListParameter(paramElement);
-				addParameter(param);
-			} else if (paramtype.equals(IntegerListParameter.TYPE)) {
-				IntegerListParameter param = new IntegerListParameter(paramElement);
-				addParameter(param);
-			} else if (paramtype.equals(FloatListParameter.TYPE)) {
-				FloatListParameter param = new FloatListParameter(paramElement);
-				addParameter(param);
-			} else if (paramtype.equals(LongListParameter.TYPE)) {
-				LongListParameter param = new LongListParameter(paramElement);
-				addParameter(param);
-			} else {
-				String msg = "What kind of parameter is this: {0}"; //$NON-NLS-1$
-				msg = MessageFormat.format(msg, paramtype);
-				throw new StrolchException(msg);
-			}
-		}
-	}
-
-	@Override
-	protected void fillElement(Element element) {
-		super.fillElement(element);
-
-		if (this.parameterMap != null) {
-			for (Parameter<?> parameter : this.parameterMap.values()) {
-				element.appendChild(parameter.toDom(element.getOwnerDocument()));
-			}
-		}
-	}
-
 	@Override
 	protected void fillClone(StrolchElement clone) {
 		super.fillClone(clone);
diff --git a/li.strolch.model/src/main/java/li/strolch/model/Resource.java b/li.strolch.model/src/main/java/li/strolch/model/Resource.java
index d028e72c4..210d16a40 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/Resource.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/Resource.java
@@ -15,7 +15,6 @@
  */
 package li.strolch.model;
 
-import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -24,22 +23,11 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
-import li.strolch.exception.StrolchException;
 import li.strolch.model.Locator.LocatorBuilder;
-import li.strolch.model.timedstate.BooleanTimedState;
-import li.strolch.model.timedstate.FloatTimedState;
-import li.strolch.model.timedstate.IntegerTimedState;
-import li.strolch.model.timedstate.StringSetTimedState;
 import li.strolch.model.timedstate.StrolchTimedState;
 import li.strolch.model.timevalue.IValue;
 import li.strolch.model.visitor.StrolchRootElementVisitor;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-import org.w3c.dom.NodeList;
-
-import ch.eitchnet.utils.dbc.DBC;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  */
@@ -67,41 +55,6 @@ public class Resource extends GroupedParameterizedElement implements StrolchRoot
 		super(id, name, type);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public Resource(Element element) {
-		super.fromDom(element);
-
-		NodeList timedStateElems = element.getElementsByTagName(Tags.TIMED_STATE);
-		for (int i = 0; i < timedStateElems.getLength(); i++) {
-			Element timedStateElem = (Element) timedStateElems.item(i);
-			String typeS = timedStateElem.getAttribute(Tags.TYPE);
-
-			DBC.PRE.assertNotEmpty("Type must be set on TimedState for resource with id " + this.id, typeS);
-
-			if (typeS.equals(FloatTimedState.TYPE)) {
-				FloatTimedState timedState = new FloatTimedState(timedStateElem);
-				addTimedState(timedState);
-			} else if (typeS.equals(IntegerTimedState.TYPE)) {
-				IntegerTimedState timedState = new IntegerTimedState(timedStateElem);
-				addTimedState(timedState);
-			} else if (typeS.equals(BooleanTimedState.TYPE)) {
-				BooleanTimedState timedState = new BooleanTimedState(timedStateElem);
-				addTimedState(timedState);
-			} else if (typeS.equals(StringSetTimedState.TYPE)) {
-				StringSetTimedState timedState = new StringSetTimedState(timedStateElem);
-				addTimedState(timedState);
-			} else {
-				String msg = "What kind of TimedState is this: {0}"; //$NON-NLS-1$
-				msg = MessageFormat.format(msg, typeS);
-				throw new StrolchException(msg);
-			}
-		}
-	}
-
 	@SuppressWarnings("unchecked")
 	public void addTimedState(StrolchTimedState<?> strolchTimedState) {
 		if (this.timedStateMap == null) {
@@ -150,22 +103,6 @@ public class Resource extends GroupedParameterizedElement implements StrolchRoot
 		return this.timedStateMap != null && this.timedStateMap.containsKey(id);
 	}
 
-	@Override
-	public Element toDom(Document doc) {
-
-		Element element = doc.createElement(Tags.RESOURCE);
-		fillElement(element);
-
-		if (this.timedStateMap != null) {
-			for (StrolchTimedState<?> state : this.timedStateMap.values()) {
-				Element timedStateElem = state.toDom(element.getOwnerDocument());
-				element.appendChild(timedStateElem);
-			}
-		}
-
-		return element;
-	}
-
 	@Override
 	public Resource getClone() {
 		Resource clone = new Resource();
@@ -202,7 +139,7 @@ public class Resource extends GroupedParameterizedElement implements StrolchRoot
 	public Resource getRootElement() {
 		return this;
 	}
-	
+
 	@Override
 	public boolean isRootElement() {
 		return true;
diff --git a/li.strolch.model/src/main/java/li/strolch/model/StrolchElement.java b/li.strolch.model/src/main/java/li/strolch/model/StrolchElement.java
index 7328bc4a8..1f3ad4734 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/StrolchElement.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/StrolchElement.java
@@ -17,9 +17,6 @@ package li.strolch.model;
 
 import java.io.Serializable;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  */
@@ -76,17 +73,6 @@ public interface StrolchElement extends Serializable, Comparable<StrolchElement>
 	 */
 	public long getDbid();
 
-	/**
-	 * Returns an {@link Element} object which is an XML representation of this object
-	 *
-	 * @param doc
-	 *            the document to which this element is being written. The client must not append to the document, the
-	 *            caller will perform this as needed
-	 *
-	 * @return
-	 */
-	public Element toDom(Document doc);
-
 	/**
 	 * Returns the type of this {@link StrolchElement}
 	 *
diff --git a/li.strolch.model/src/main/java/li/strolch/model/StrolchValueType.java b/li.strolch.model/src/main/java/li/strolch/model/StrolchValueType.java
new file mode 100644
index 000000000..160731a7d
--- /dev/null
+++ b/li.strolch.model/src/main/java/li/strolch/model/StrolchValueType.java
@@ -0,0 +1,374 @@
+/*
+ * Copyright 2015 Robert von Burg <eitch@eitchnet.ch>
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package li.strolch.model;
+
+import java.text.MessageFormat;
+
+import li.strolch.model.parameter.BooleanParameter;
+import li.strolch.model.parameter.DateParameter;
+import li.strolch.model.parameter.DurationParameter;
+import li.strolch.model.parameter.FloatListParameter;
+import li.strolch.model.parameter.FloatParameter;
+import li.strolch.model.parameter.IntegerListParameter;
+import li.strolch.model.parameter.IntegerParameter;
+import li.strolch.model.parameter.LongListParameter;
+import li.strolch.model.parameter.LongParameter;
+import li.strolch.model.parameter.Parameter;
+import li.strolch.model.parameter.StringListParameter;
+import li.strolch.model.parameter.StringParameter;
+import li.strolch.model.timedstate.BooleanTimedState;
+import li.strolch.model.timedstate.FloatTimedState;
+import li.strolch.model.timedstate.IntegerTimedState;
+import li.strolch.model.timedstate.StringSetTimedState;
+import li.strolch.model.timedstate.StrolchTimedState;
+import li.strolch.model.timedstate.TimedState;
+import li.strolch.model.timevalue.IValue;
+import li.strolch.model.timevalue.IValueChange;
+import li.strolch.model.timevalue.impl.BooleanValue;
+import li.strolch.model.timevalue.impl.FloatValue;
+import li.strolch.model.timevalue.impl.IntegerValue;
+import li.strolch.model.timevalue.impl.StringSetValue;
+
+public enum StrolchValueType {
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * <li>{@link TimedState}</li>
+	 * <li>{@link IValue}</li>
+	 * <li>{@link IValueChange}</li>
+	 * </ul>
+	 */
+	BOOLEAN("Boolean") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new BooleanParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			return new BooleanTimedState();
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			return new BooleanValue(valueAsString);
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * <li>{@link TimedState}</li>
+	 * <li>{@link IValue}</li>
+	 * <li>{@link IValueChange}</li>
+	 * </ul>
+	 */
+	INTEGER("Integer") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new IntegerParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			return new IntegerTimedState();
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			return new IntegerValue(valueAsString);
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * <li>{@link TimedState}</li>
+	 * <li>{@link IValue}</li>
+	 * <li>{@link IValueChange}</li>
+	 * </ul>
+	 */
+	FLOAT("Float") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new FloatParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			return new FloatTimedState();
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			return new FloatValue(valueAsString);
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * </ul>
+	 */
+	LONG("Long") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new LongParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"TimeStates of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"Parameters of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * </ul>
+	 */
+	STRING("String") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new StringParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"TimeStates of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"Parameters of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * </ul>
+	 */
+	DATE("Date") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new DateParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"TimeStates of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"Parameters of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * </ul>
+	 */
+	DURATION("Duration") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new DurationParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"TimeStates of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"Parameters of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * </ul>
+	 */
+	FLOAT_LIST("FloatList") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new FloatListParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"TimeStates of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"Parameters of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * </ul>
+	 */
+	INTEGER_LIST("IntegerList") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new IntegerListParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"TimeStates of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"Parameters of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * </ul>
+	 */
+	LONG_LIST("LongList") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new LongListParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"TimeStates of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"Parameters of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link Parameter}</li>
+	 * </ul>
+	 */
+	STRING_LIST("StringList") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			return new StringListParameter();
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"TimeStates of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"Values of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+	},
+
+	/**
+	 * Can be used for:<br />
+	 * <ul>
+	 * <li>{@link TimedState}</li>
+	 * <li>{@link IValue}</li>
+	 * <li>{@link IValueChange}</li>
+	 * </ul>
+	 */
+	STRING_SET("StringSet") {
+		@Override
+		public Parameter<?> parameterInstance() {
+			throw new UnsupportedOperationException(MessageFormat.format(
+					"Parameters of type {0} are not supported!", getType())); //$NON-NLS-1$
+		}
+
+		@Override
+		public StrolchTimedState<? extends IValue<?>> timedStateInstance() {
+			return new StringSetTimedState();
+		}
+
+		@Override
+		public IValue<?> valueInstance(String valueAsString) {
+			return new StringSetValue(valueAsString);
+		}
+	};
+
+	private String type;
+
+	private StrolchValueType(String type) {
+		this.type = type;
+	}
+
+	public String getType() {
+		return this.type;
+	}
+
+	public static StrolchValueType parse(String value) {
+		for (StrolchValueType type : StrolchValueType.values()) {
+			if (type.type.equals(value))
+				return type;
+		}
+		throw new IllegalArgumentException("Type " + value + " does not exist!");
+	}
+
+	public abstract Parameter<?> parameterInstance();
+
+	public abstract StrolchTimedState<? extends IValue<?>> timedStateInstance();
+
+	public abstract IValue<?> valueInstance(String valueAsString);
+}
\ No newline at end of file
diff --git a/li.strolch.model/src/main/java/li/strolch/model/Tags.java b/li.strolch.model/src/main/java/li/strolch/model/Tags.java
index 92974fa20..d14fd3408 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/Tags.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/Tags.java
@@ -41,19 +41,17 @@ public class Tags {
 	public static final String FILE = "file";
 	public static final String BAG = "Bag";
 	public static final String AUDIT = "Audit";
-	
+
 	public static final String ACTIVITY = "Activity";
 	public static final String ACTION = "Action";
 	public static final String START = "Start";
 	public static final String END = "End";
 	public static final String VALUE_CHANGE = "ValueChange";
-	public static final String VALUE_CLASS = "Class";
 	public static final String RESOURCE_ID = "ResourceId";
 	public static final String RESOURCE_TYPE = "ResourceType";
 	public static final String STATE_ID = "StateId";
-	
 
-	public class Audit {
+	public static class Audit {
 		public static final String ID = Tags.ID;
 
 		public static final String USERNAME = "Username";
diff --git a/li.strolch.model/src/main/java/li/strolch/model/activity/Action.java b/li.strolch.model/src/main/java/li/strolch/model/activity/Action.java
index 4da30b4a6..412fa1c5a 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/activity/Action.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/activity/Action.java
@@ -18,6 +18,8 @@ package li.strolch.model.activity;
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
+import java.util.Iterator;
 import java.util.List;
 
 import li.strolch.model.GroupedParameterizedElement;
@@ -27,17 +29,13 @@ import li.strolch.model.Resource;
 import li.strolch.model.State;
 import li.strolch.model.StrolchElement;
 import li.strolch.model.StrolchRootElement;
-import li.strolch.model.Tags;
+import li.strolch.model.timevalue.IValue;
 import li.strolch.model.timevalue.IValueChange;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-
 /**
- * An {@link Action} represents a single step within an {@link Activity}, that
- * is, one that is not further decomposed within the {@link Activity}. A
- * {@link Activity} applies {@link IValueChange} objects at the start and end
- * time of the {@link Activity}.
+ * An {@link Action} represents a single step within an {@link Activity}, that is, one that is not further decomposed
+ * within the {@link Activity}. A {@link Activity} applies {@link IValueChange} objects at the start and end time of the
+ * {@link Activity}.
  * 
  * @author Martin Smock <martin.smock@bluewin.ch>
  */
@@ -46,13 +44,20 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 	protected static final long serialVersionUID = 1L;
 
 	protected Activity parent;
-	protected String resourceId, resourceType;
-	protected State state = State.CREATED;
+	protected String resourceId;
+	protected String resourceType;
+	protected State state;
 
-	protected final List<IValueChange<?>> changes = new ArrayList<>();
+	protected List<IValueChange<? extends IValue<?>>> changes;
 
 	public Action(String id, String name, String type) {
 		super(id, name, type);
+		this.state = State.CREATED;
+	}
+
+	private void initChanges() {
+		if (this.changes == null)
+			this.changes = new ArrayList<>();
 	}
 
 	/**
@@ -86,8 +91,7 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 	}
 
 	/**
-	 * @return the type of the <code>Resource</code> this <code>Action</code>
-	 *         acts on
+	 * @return the type of the <code>Resource</code> this <code>Action</code> acts on
 	 */
 	public String getResourceType() {
 		return this.resourceType;
@@ -100,25 +104,41 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 		this.resourceType = resourceType;
 	}
 
+	/**
+	 * Returns true if this {@link Action} contains any {@link IValueChange changes}, false if not
+	 * 
+	 * @return true if this {@link Action} contains any {@link IValueChange changes}, false if not
+	 */
+	public boolean hasChanges() {
+		return this.changes != null && !this.changes.isEmpty();
+	}
+
 	/**
 	 * @param add
-	 *            <code>IValueChange</code> to be applied to the
-	 *            <code>Resource</code>
+	 *            <code>IValueChange</code> to be applied to the <code>Resource</code>
 	 * 
 	 * @return <tt>true</tt> (as specified by {@link Collection#add})
 	 */
-	public boolean addChange(IValueChange<?> change) {
+	public boolean addChange(IValueChange<? extends IValue<?>> change) {
+		initChanges();
 		return changes.add(change);
 	}
 
 	/**
-	 * @return the list of <code>IValueChange</code> attached to the
-	 *         <code>Action</code> start
+	 * @return the list of <code>IValueChange</code> attached to the <code>Action</code> start
 	 */
-	public List<IValueChange<?>> getChanges() {
+	public List<IValueChange<? extends IValue<?>>> getChanges() {
+		if (this.changes == null)
+			return Collections.emptyList();
 		return changes;
 	}
 
+	public Iterator<IValueChange<? extends IValue<?>>> changesIterator() {
+		if (this.changes == null)
+			return Collections.<IValueChange<? extends IValue<?>>> emptyList().iterator();
+		return this.changes.iterator();
+	}
+
 	@Override
 	public StrolchElement getParent() {
 		return parent;
@@ -135,14 +155,16 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 	}
 
 	@Override
-	public StrolchElement getClone() {
+	public Action getClone() {
 		Action clone = new Action(getId(), getName(), getType());
 		clone.setDbid(getDbid());
 		clone.setResourceId(resourceId);
 		clone.setResourceType(resourceType);
 		clone.setState(state);
-		for (IValueChange<?> change : getChanges()) {
-			clone.changes.add(change.getClone());
+		if (this.changes != null) {
+			for (IValueChange<? extends IValue<?>> change : getChanges()) {
+				clone.addChange(change.getClone());
+			}
 		}
 		return clone;
 	}
@@ -185,6 +207,8 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 	@Override
 	public Long getStart() {
 		Long start = Long.MAX_VALUE;
+		if (this.changes == null)
+			return start;
 		for (IValueChange<?> change : changes) {
 			start = Math.min(start, change.getTime());
 		}
@@ -194,23 +218,11 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 	@Override
 	public Long getEnd() {
 		Long end = 0L;
+		if (this.changes == null)
+			return end;
 		for (IValueChange<?> change : changes) {
 			end = Math.max(end, change.getTime());
 		}
 		return end;
 	}
-
-	@Override
-	public Element toDom(Document doc) {
-		Element element = doc.createElement(Tags.ACTION);
-		fillElement(element);
-		element.setAttribute(Tags.STATE, this.state.toString());
-		element.setAttribute(Tags.RESOURCE_ID, this.resourceId);
-		element.setAttribute(Tags.RESOURCE_TYPE, this.resourceType);
-		for (IValueChange<?> change : changes) {
-			element.appendChild(change.toDom(doc));
-		}
-		return element;
-	}
-
 }
diff --git a/li.strolch.model/src/main/java/li/strolch/model/activity/Activity.java b/li.strolch.model/src/main/java/li/strolch/model/activity/Activity.java
index f550814d8..7b24948d3 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/activity/Activity.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/activity/Activity.java
@@ -15,6 +15,7 @@
  */
 package li.strolch.model.activity;
 
+import java.util.Collections;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.Map;
@@ -30,12 +31,9 @@ import li.strolch.model.StrolchRootElement;
 import li.strolch.model.Tags;
 import li.strolch.model.visitor.StrolchRootElementVisitor;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-
 /**
- * Parameterized object grouping a collection of {@link Activity} and
- * {@link Action} objects defining the process to be scheduled
+ * Parameterized object grouping a collection of {@link Activity} and {@link Action} objects defining the process to be
+ * scheduled
  * 
  * @author Martin Smock <martin.smock@bluewin.ch>
  */
@@ -45,27 +43,37 @@ public class Activity extends GroupedParameterizedElement implements IActivityEl
 
 	protected Activity parent;
 
+	protected Map<String, IActivityElement> elements;
+
 	public Activity(String id, String name, String type) {
 		super(id, name, type);
 	}
 
-	// use a LinkedHashMap since we will iterate elements in the order added and
-	// lookup elements by ID
-	protected Map<String, IActivityElement> elements = new LinkedHashMap<String, IActivityElement>();
+	private void initElements() {
+		if (this.elements == null) {
+			// use a LinkedHashMap since we will iterate elements in the order added and lookup elements by ID
+			elements = new LinkedHashMap<String, IActivityElement>();
+		}
+	}
+
+	public boolean hasElements() {
+		return this.elements != null && !this.elements.isEmpty();
+	}
 
 	/**
-	 * add an activity element to the <code>LinkedHashMap</code> of
-	 * <code>IActivityElements</code>
+	 * add an activity element to the <code>LinkedHashMap</code> of <code>IActivityElements</code>
 	 * 
 	 * @param activityElement
 	 * @return the element added
 	 */
 	public IActivityElement addElement(IActivityElement activityElement) {
+		initElements();
 		String id = activityElement.getId();
 		if (id == null)
 			throw new StrolchException("Cannot add IActivityElement without id.");
 		else if (elements.containsKey(id))
-			throw new StrolchException("Activiy " + getLocator() + " already contains an activity element with id = " + id);
+			throw new StrolchException("Activiy " + getLocator() + " already contains an activity element with id = "
+					+ id);
 		else {
 			activityElement.setParent(this);
 			return elements.put(activityElement.getId(), activityElement);
@@ -80,27 +88,33 @@ public class Activity extends GroupedParameterizedElement implements IActivityEl
 	 * @return IActivityElement
 	 */
 	public IActivityElement getElement(String id) {
+		if (this.elements == null)
+			return null;
 		return elements.get(id);
 	}
 
 	/**
-	 * @return get the <code>LinkedHashMap</code> of
-	 *         <code>IActivityElements</code>
+	 * @return get the <code>LinkedHashMap</code> of <code>IActivityElements</code>
 	 */
 	public Map<String, IActivityElement> getElements() {
+		if (this.elements == null)
+			return Collections.emptyMap();
 		return elements;
 	}
 
 	/**
-	 * @return the iterator for entries, which include the id as key and the
-	 *         {@link IActivityElement} as value
+	 * @return the iterator for entries, which include the id as key and the {@link IActivityElement} as value
 	 */
 	public Iterator<Entry<String, IActivityElement>> elementIterator() {
+		if (this.elements == null)
+			return Collections.<String, IActivityElement> emptyMap().entrySet().iterator();
 		return elements.entrySet().iterator();
 	}
 
 	public Long getStart() {
 		Long start = Long.MAX_VALUE;
+		if (this.elements == null)
+			return start;
 		Iterator<Entry<String, IActivityElement>> elementIterator = elementIterator();
 		while (elementIterator.hasNext()) {
 			IActivityElement action = elementIterator.next().getValue();
@@ -111,6 +125,8 @@ public class Activity extends GroupedParameterizedElement implements IActivityEl
 
 	public Long getEnd() {
 		Long end = 0L;
+		if (this.elements == null)
+			return end;
 		Iterator<Entry<String, IActivityElement>> elementIterator = elementIterator();
 		while (elementIterator.hasNext()) {
 			IActivityElement action = elementIterator.next().getValue();
@@ -121,6 +137,8 @@ public class Activity extends GroupedParameterizedElement implements IActivityEl
 
 	public State getState() {
 		State state = State.PLANNED;
+		if (this.elements == null)
+			return state;
 		Iterator<Entry<String, IActivityElement>> elementIterator = elementIterator();
 		while (elementIterator.hasNext()) {
 			IActivityElement child = elementIterator.next().getValue();
@@ -144,18 +162,6 @@ public class Activity extends GroupedParameterizedElement implements IActivityEl
 		locatorBuilder.append(Tags.ACTIVITY).append(getType()).append(getId());
 	}
 
-	@Override
-	public Element toDom(Document doc) {
-		Element element = doc.createElement(Tags.ACTIVITY);
-		fillElement(element);
-		Iterator<Entry<String, IActivityElement>> elementIterator = elementIterator();
-		while (elementIterator.hasNext()) {
-			IActivityElement activityElement = elementIterator.next().getValue();
-			element.appendChild(activityElement.toDom(doc)); 
-		}
-		return element;
-	}
-
 	@Override
 	public StrolchElement getParent() {
 		return parent;
@@ -172,12 +178,12 @@ public class Activity extends GroupedParameterizedElement implements IActivityEl
 	}
 
 	@Override
-	public StrolchElement getClone() {
+	public Activity getClone() {
 		Activity clone = new Activity(id, name, type);
-		Iterator<Entry<String, IActivityElement>> elementIterator = elementIterator();
-		while (elementIterator.hasNext()) {
-			Entry<String, IActivityElement> next = elementIterator.next();
-			clone.elements.put(next.getKey(), (IActivityElement) next.getValue().getClone());
+		if (this.elements == null)
+			return clone;
+		for (IActivityElement element : this.elements.values()) {
+			clone.addElement(element.getClone());
 		}
 		return clone;
 	}
@@ -210,5 +216,4 @@ public class Activity extends GroupedParameterizedElement implements IActivityEl
 	public void setParent(Activity activity) {
 		this.parent = activity;
 	}
-
 }
diff --git a/li.strolch.model/src/main/java/li/strolch/model/activity/IActivityElement.java b/li.strolch.model/src/main/java/li/strolch/model/activity/IActivityElement.java
index 226d52763..0bee8af39 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/activity/IActivityElement.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/activity/IActivityElement.java
@@ -22,16 +22,16 @@ import li.strolch.model.StrolchElement;
  * Marker for all child elements of {@link Activity} objects
  * 
  * @author Martin Smock <martin.smock@bluewin.ch>
- * 
  */
 public interface IActivityElement extends StrolchElement {
 
-	Long getStart();
+	public Long getStart();
 
-	Long getEnd();
+	public Long getEnd();
 
-	State getState();
-	
-	void setParent(Activity activity); 
+	public State getState();
 
+	public void setParent(Activity activity);
+
+	public IActivityElement getClone();
 }
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/AbstractParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/AbstractParameter.java
index 04110f754..b5e2c2506 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/AbstractParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/AbstractParameter.java
@@ -26,12 +26,7 @@ import li.strolch.model.Locator;
 import li.strolch.model.Locator.LocatorBuilder;
 import li.strolch.model.ParameterizedElement;
 import li.strolch.model.StrolchRootElement;
-import li.strolch.model.Tags;
 import li.strolch.model.visitor.ParameterVisitor;
-
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-
 import ch.eitchnet.utils.helper.StringHelper;
 
 /**
@@ -135,74 +130,6 @@ public abstract class AbstractParameter<T> extends AbstractStrolchElement implem
 		return false;
 	}
 
-	@Override
-	public Element toDom(Document doc) {
-		Element element = doc.createElement(Tags.PARAMETER);
-		fillElement(element);
-
-		element.setAttribute(Tags.VALUE, getValueAsString());
-
-		if (!this.interpretation.equals(INTERPRETATION_NONE)) {
-			element.setAttribute(Tags.INTERPRETATION, this.interpretation);
-		}
-		if (!this.uom.equals(UOM_NONE)) {
-			element.setAttribute(Tags.UOM, this.uom);
-		}
-		if (this.hidden) {
-			element.setAttribute(Tags.HIDDEN, Boolean.toString(this.hidden));
-		}
-		if (this.index != 0) {
-			element.setAttribute(Tags.INDEX, Integer.toString(this.index));
-		}
-
-		return element;
-	}
-
-	@Override
-	public void fromDom(Element element) {
-
-		super.fromDom(element);
-
-		String typeS = element.getAttribute(Tags.TYPE);
-		if (StringHelper.isEmpty(typeS)) {
-			String msg = "Type must be set on element with id {0}"; //$NON-NLS-1$
-			msg = MessageFormat.format(msg, this.id);
-			throw new StrolchException(msg);
-		} else if (!typeS.equals(getType())) {
-			String msg = "{0} must have type {1}, not: {2}"; //$NON-NLS-1$
-			msg = MessageFormat.format(msg, getClass().getSimpleName(), getType(), typeS);
-			throw new StrolchException(msg);
-		}
-
-		String interpretation = element.getAttribute(Tags.INTERPRETATION);
-		String hidden = element.getAttribute(Tags.HIDDEN);
-		String uom = element.getAttribute(Tags.UOM);
-		String index = element.getAttribute(Tags.INDEX);
-
-		setInterpretation(interpretation);
-		setUom(uom);
-
-		if (StringHelper.isEmpty(index)) {
-			this.index = 0;
-		} else {
-			this.index = Integer.valueOf(index);
-		}
-
-		if (StringHelper.isEmpty(hidden)) {
-			setHidden(false);
-		} else {
-			if (hidden.equalsIgnoreCase(Boolean.TRUE.toString())) {
-				setHidden(true);
-			} else if (hidden.equalsIgnoreCase(Boolean.FALSE.toString())) {
-				setHidden(false);
-			} else {
-				String msg = "Boolean string must be either {0} or {1}"; //$NON-NLS-1$
-				msg = MessageFormat.format(msg, Boolean.TRUE.toString(), Boolean.FALSE.toString());
-				throw new StrolchException(msg);
-			}
-		}
-	}
-
 	@Override
 	protected void fillLocator(LocatorBuilder lb) {
 		lb.append(this.id);
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/BooleanParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/BooleanParameter.java
index 56c1aba28..8f1ada4ab 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/BooleanParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/BooleanParameter.java
@@ -15,14 +15,8 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
-
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
-
-import org.w3c.dom.Element;
-
 import ch.eitchnet.utils.helper.StringHelper;
 
 /**
@@ -30,7 +24,6 @@ import ch.eitchnet.utils.helper.StringHelper;
  */
 public class BooleanParameter extends AbstractParameter<Boolean> {
 
-	public static final String TYPE = "Boolean"; //$NON-NLS-1$
 	private static final long serialVersionUID = 0L;
 
 	private Boolean value = Boolean.FALSE;
@@ -54,23 +47,6 @@ public class BooleanParameter extends AbstractParameter<Boolean> {
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 * 
-	 * @param element
-	 */
-	public BooleanParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(parseFromString(valueS));
-	}
-
 	@Override
 	public String getValueAsString() {
 		return this.value.toString();
@@ -87,9 +63,14 @@ public class BooleanParameter extends AbstractParameter<Boolean> {
 		this.value = value;
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(parseFromString(valueAsString));
+	}
+
 	@Override
 	public String getType() {
-		return BooleanParameter.TYPE;
+		return StrolchValueType.BOOLEAN.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/DateParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/DateParameter.java
index ffffb8462..461319b6f 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/DateParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/DateParameter.java
@@ -15,16 +15,10 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
 import java.util.Date;
 
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
-
-import org.w3c.dom.Element;
-
-import ch.eitchnet.utils.helper.StringHelper;
 import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
 
 /**
@@ -32,7 +26,6 @@ import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
  */
 public class DateParameter extends AbstractParameter<Date> {
 
-	public static final String TYPE = "Date"; //$NON-NLS-1$
 	private static final long serialVersionUID = 0L;
 
 	private Date value;
@@ -56,23 +49,6 @@ public class DateParameter extends AbstractParameter<Date> {
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public DateParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(parseFromString(valueS));
-	}
-
 	@Override
 	public String getValueAsString() {
 		return ISO8601FormatFactory.getInstance().formatDate(this.value);
@@ -89,9 +65,14 @@ public class DateParameter extends AbstractParameter<Date> {
 		this.value = value;
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(parseFromString(valueAsString));
+	}
+
 	@Override
 	public String getType() {
-		return DateParameter.TYPE;
+		return StrolchValueType.DATE.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/DurationParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/DurationParameter.java
index 626ce8635..2916d7aff 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/DurationParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/DurationParameter.java
@@ -15,15 +15,8 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
-
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
-
-import org.w3c.dom.Element;
-
-import ch.eitchnet.utils.helper.StringHelper;
 import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
 
 /**
@@ -31,7 +24,6 @@ import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
  */
 public class DurationParameter extends AbstractParameter<Long> {
 
-	public static final String TYPE = "Duration"; //$NON-NLS-1$
 	private static final long serialVersionUID = 0L;
 
 	private Long value;
@@ -55,23 +47,6 @@ public class DurationParameter extends AbstractParameter<Long> {
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public DurationParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(parseFromString(valueS));
-	}
-
 	@Override
 	public String getValueAsString() {
 		return ISO8601FormatFactory.getInstance().formatDuration(this.value);
@@ -88,9 +63,14 @@ public class DurationParameter extends AbstractParameter<Long> {
 		this.value = value;
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(parseFromString(valueAsString));
+	}
+
 	@Override
 	public String getType() {
-		return DurationParameter.TYPE;
+		return StrolchValueType.DURATION.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatListParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatListParameter.java
index 83240a518..5bee81921 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatListParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatListParameter.java
@@ -15,18 +15,13 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
-
-import org.w3c.dom.Element;
-
 import ch.eitchnet.utils.helper.StringHelper;
 
 /**
@@ -34,7 +29,6 @@ import ch.eitchnet.utils.helper.StringHelper;
  */
 public class FloatListParameter extends AbstractParameter<List<Double>> implements ListParameter<Double> {
 
-	public static final String TYPE = "FloatList"; //$NON-NLS-1$
 	private static final long serialVersionUID = 1L;
 
 	protected List<Double> value;
@@ -59,23 +53,6 @@ public class FloatListParameter extends AbstractParameter<List<Double>> implemen
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public FloatListParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(parseFromString(valueS));
-	}
-
 	@Override
 	public String getValueAsString() {
 		if (this.value.isEmpty()) {
@@ -111,6 +88,11 @@ public class FloatListParameter extends AbstractParameter<List<Double>> implemen
 		this.value.addAll(value);
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(parseFromString(valueAsString));
+	}
+
 	@Override
 	public void addValue(Double value) {
 		this.value.add(value);
@@ -133,7 +115,7 @@ public class FloatListParameter extends AbstractParameter<List<Double>> implemen
 
 	@Override
 	public String getType() {
-		return TYPE;
+		return StrolchValueType.FLOAT_LIST.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatParameter.java
index 565ce2738..f9c408ea1 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/FloatParameter.java
@@ -15,23 +15,15 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
-
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
 
-import org.w3c.dom.Element;
-
-import ch.eitchnet.utils.helper.StringHelper;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  *
  */
 public class FloatParameter extends AbstractParameter<Double> {
 
-	public static final String TYPE = "Float"; //$NON-NLS-1$
 	private static final long serialVersionUID = 0L;
 
 	private Double value = Double.MAX_VALUE;
@@ -56,23 +48,6 @@ public class FloatParameter extends AbstractParameter<Double> {
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public FloatParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(parseFromString(valueS));
-	}
-
 	@Override
 	public String getValueAsString() {
 		return Double.toString(this.value);
@@ -89,9 +64,14 @@ public class FloatParameter extends AbstractParameter<Double> {
 		this.value = value;
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(parseFromString(valueAsString));
+	}
+
 	@Override
 	public String getType() {
-		return FloatParameter.TYPE;
+		return StrolchValueType.FLOAT.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerListParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerListParameter.java
index 7ee9dfb78..47fc8f55b 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerListParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerListParameter.java
@@ -15,18 +15,13 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
-
-import org.w3c.dom.Element;
-
 import ch.eitchnet.utils.helper.StringHelper;
 
 /**
@@ -34,7 +29,6 @@ import ch.eitchnet.utils.helper.StringHelper;
  */
 public class IntegerListParameter extends AbstractParameter<List<Integer>> implements ListParameter<Integer> {
 
-	public static final String TYPE = "IntegerList"; //$NON-NLS-1$
 	private static final long serialVersionUID = 1L;
 
 	protected List<Integer> value;
@@ -59,23 +53,6 @@ public class IntegerListParameter extends AbstractParameter<List<Integer>> imple
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public IntegerListParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(parseFromString(valueS));
-	}
-
 	@Override
 	public String getValueAsString() {
 		if (this.value.isEmpty()) {
@@ -111,6 +88,11 @@ public class IntegerListParameter extends AbstractParameter<List<Integer>> imple
 		this.value.addAll(value);
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(parseFromString(valueAsString));
+	}
+
 	@Override
 	public void addValue(Integer value) {
 		this.value.add(value);
@@ -133,7 +115,7 @@ public class IntegerListParameter extends AbstractParameter<List<Integer>> imple
 
 	@Override
 	public String getType() {
-		return TYPE;
+		return StrolchValueType.INTEGER_LIST.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerParameter.java
index cf29997d4..333a2aae4 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/IntegerParameter.java
@@ -15,23 +15,15 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
-
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
 
-import org.w3c.dom.Element;
-
-import ch.eitchnet.utils.helper.StringHelper;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  *
  */
 public class IntegerParameter extends AbstractParameter<Integer> {
 
-	public static final String TYPE = "Integer"; //$NON-NLS-1$
 	private static final long serialVersionUID = 0L;
 
 	private Integer value = Integer.MAX_VALUE;
@@ -55,26 +47,9 @@ public class IntegerParameter extends AbstractParameter<Integer> {
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public IntegerParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(parseFromString(valueS));
-	}
-
 	@Override
 	public String getType() {
-		return IntegerParameter.TYPE;
+		return StrolchValueType.INTEGER.getType();
 	}
 
 	@Override
@@ -93,6 +68,11 @@ public class IntegerParameter extends AbstractParameter<Integer> {
 		this.value = value;
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(parseFromString(valueAsString));
+	}
+
 	@Override
 	public IntegerParameter getClone() {
 		IntegerParameter clone = new IntegerParameter();
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/LongListParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/LongListParameter.java
index 941b7ccf6..a5be57b2c 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/LongListParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/LongListParameter.java
@@ -15,18 +15,13 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
-
-import org.w3c.dom.Element;
-
 import ch.eitchnet.utils.helper.StringHelper;
 
 /**
@@ -34,7 +29,6 @@ import ch.eitchnet.utils.helper.StringHelper;
  */
 public class LongListParameter extends AbstractParameter<List<Long>> implements ListParameter<Long> {
 
-	public static final String TYPE = "LongList"; //$NON-NLS-1$
 	private static final long serialVersionUID = 1L;
 
 	protected List<Long> value;
@@ -59,23 +53,6 @@ public class LongListParameter extends AbstractParameter<List<Long>> implements
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public LongListParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(parseFromString(valueS));
-	}
-
 	@Override
 	public String getValueAsString() {
 		if (this.value.isEmpty()) {
@@ -111,6 +88,11 @@ public class LongListParameter extends AbstractParameter<List<Long>> implements
 		this.value.addAll(value);
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(parseFromString(valueAsString));
+	}
+
 	@Override
 	public void addValue(Long value) {
 		this.value.add(value);
@@ -133,7 +115,7 @@ public class LongListParameter extends AbstractParameter<List<Long>> implements
 
 	@Override
 	public String getType() {
-		return TYPE;
+		return StrolchValueType.LONG_LIST.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/LongParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/LongParameter.java
index 0e47f51a9..443daf743 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/LongParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/LongParameter.java
@@ -15,23 +15,15 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
-
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
 
-import org.w3c.dom.Element;
-
-import ch.eitchnet.utils.helper.StringHelper;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  *
  */
 public class LongParameter extends AbstractParameter<Long> {
 
-	public static final String TYPE = "Long"; //$NON-NLS-1$
 	private static final long serialVersionUID = 0L;
 
 	protected Long value;
@@ -55,23 +47,6 @@ public class LongParameter extends AbstractParameter<Long> {
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public LongParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(parseFromString(valueS));
-	}
-
 	@Override
 	public String getValueAsString() {
 		return this.value.toString();
@@ -88,9 +63,14 @@ public class LongParameter extends AbstractParameter<Long> {
 		this.value = value;
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(parseFromString(valueAsString));
+	}
+
 	@Override
 	public String getType() {
-		return LongParameter.TYPE;
+		return StrolchValueType.LONG.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/Parameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/Parameter.java
index f55b99594..c6ecde5dd 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/Parameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/Parameter.java
@@ -26,12 +26,20 @@ import li.strolch.model.visitor.ParameterVisitor;
 public interface Parameter<T> extends StrolchElement {
 
 	/**
-	 * the value of the parameter as string
+	 * Returns the value of the parameter as string
 	 * 
-	 * @return String
+	 * @return the value as string
 	 */
 	public String getValueAsString();
 
+	/**
+	 * Set the value of the parameter from a string
+	 * 
+	 * @param valueAsString
+	 *            the string from which to set the value
+	 */
+	public void setValueFromString(String valueAsString);
+
 	/**
 	 * the value of the parameter
 	 * 
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/StringListParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/StringListParameter.java
index b19c008cb..323506efb 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/StringListParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/StringListParameter.java
@@ -15,18 +15,13 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
-
-import org.w3c.dom.Element;
-
 import ch.eitchnet.utils.helper.StringHelper;
 
 /**
@@ -34,7 +29,6 @@ import ch.eitchnet.utils.helper.StringHelper;
  */
 public class StringListParameter extends AbstractParameter<List<String>> implements ListParameter<String> {
 
-	public static final String TYPE = "StringList"; //$NON-NLS-1$
 	private static final long serialVersionUID = 1L;
 
 	protected List<String> value;
@@ -59,23 +53,6 @@ public class StringListParameter extends AbstractParameter<List<String>> impleme
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public StringListParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(parseFromString(valueS));
-	}
-
 	@Override
 	public String getValueAsString() {
 		if (this.value.isEmpty()) {
@@ -111,6 +88,11 @@ public class StringListParameter extends AbstractParameter<List<String>> impleme
 		this.value.addAll(value);
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(parseFromString(valueAsString));
+	}
+
 	@Override
 	public void addValue(String value) {
 		this.value.add(value);
@@ -133,7 +115,7 @@ public class StringListParameter extends AbstractParameter<List<String>> impleme
 
 	@Override
 	public String getType() {
-		return TYPE;
+		return StrolchValueType.STRING_LIST.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/parameter/StringParameter.java b/li.strolch.model/src/main/java/li/strolch/model/parameter/StringParameter.java
index b7c65b897..81c3e7882 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/parameter/StringParameter.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/parameter/StringParameter.java
@@ -15,16 +15,9 @@
  */
 package li.strolch.model.parameter;
 
-import java.text.MessageFormat;
-
-import li.strolch.exception.StrolchException;
-import li.strolch.model.Tags;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.visitor.ParameterVisitor;
 
-import org.w3c.dom.Element;
-
-import ch.eitchnet.utils.helper.StringHelper;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  *
@@ -32,7 +25,6 @@ import ch.eitchnet.utils.helper.StringHelper;
 public class StringParameter extends AbstractParameter<String> {
 
 	public static final String UNDEFINED_VALUE = "-"; //$NON-NLS-1$
-	public static final String TYPE = "String"; //$NON-NLS-1$
 	private static final long serialVersionUID = 0L;
 
 	private String value = UNDEFINED_VALUE;
@@ -57,26 +49,9 @@ public class StringParameter extends AbstractParameter<String> {
 		setValue(value);
 	}
 
-	/**
-	 * DOM Constructor
-	 *
-	 * @param element
-	 */
-	public StringParameter(Element element) {
-		super.fromDom(element);
-
-		String valueS = element.getAttribute(Tags.VALUE);
-		if (StringHelper.isEmpty(valueS)) {
-			String msg = MessageFormat.format("No value defined for {0}", this.id); //$NON-NLS-1$
-			throw new StrolchException(msg);
-		}
-
-		setValue(valueS);
-	}
-
 	@Override
 	public String getType() {
-		return StringParameter.TYPE;
+		return StrolchValueType.STRING.getType();
 	}
 
 	@Override
@@ -95,6 +70,11 @@ public class StringParameter extends AbstractParameter<String> {
 		this.value = value;
 	}
 
+	@Override
+	public void setValueFromString(String valueAsString) {
+		setValue(valueAsString);
+	}
+
 	@Override
 	public StringParameter getClone() {
 		StringParameter clone = new StringParameter();
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timedstate/AbstractStrolchTimedState.java b/li.strolch.model/src/main/java/li/strolch/model/timedstate/AbstractStrolchTimedState.java
index 4dbd1f1eb..ca27e5365 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timedstate/AbstractStrolchTimedState.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timedstate/AbstractStrolchTimedState.java
@@ -17,10 +17,6 @@ package li.strolch.model.timedstate;
 
 import static li.strolch.model.StrolchModelConstants.INTERPRETATION_NONE;
 import static li.strolch.model.StrolchModelConstants.UOM_NONE;
-
-import java.text.MessageFormat;
-
-import li.strolch.exception.StrolchException;
 import li.strolch.model.AbstractStrolchElement;
 import li.strolch.model.Locator;
 import li.strolch.model.Locator.LocatorBuilder;
@@ -33,10 +29,6 @@ import li.strolch.model.timevalue.ITimeVariable;
 import li.strolch.model.timevalue.IValue;
 import li.strolch.model.timevalue.IValueChange;
 import li.strolch.model.visitor.TimedStateVisitor;
-
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-
 import ch.eitchnet.utils.helper.StringHelper;
 
 /**
@@ -160,72 +152,6 @@ public abstract class AbstractStrolchTimedState<T extends IValue> extends Abstra
 		return false;
 	}
 
-	@Override
-	public Element toDom(Document doc) {
-		Element element = doc.createElement(Tags.PARAMETER);
-		fillElement(element);
-
-		if (!this.interpretation.equals(INTERPRETATION_NONE)) {
-			element.setAttribute(Tags.INTERPRETATION, this.interpretation);
-		}
-		if (!this.uom.equals(UOM_NONE)) {
-			element.setAttribute(Tags.UOM, this.uom);
-		}
-		if (this.hidden) {
-			element.setAttribute(Tags.HIDDEN, Boolean.toString(this.hidden));
-		}
-		if (this.index != 0) {
-			element.setAttribute(Tags.INDEX, Integer.toString(this.index));
-		}
-
-		return element;
-	}
-
-	@Override
-	public void fromDom(Element element) {
-
-		super.fromDom(element);
-
-		String typeS = element.getAttribute(Tags.TYPE);
-		if (StringHelper.isEmpty(typeS)) {
-			String msg = "Type must be set on element with id {0}"; //$NON-NLS-1$
-			msg = MessageFormat.format(msg, this.id);
-			throw new StrolchException(msg);
-		} else if (!typeS.equals(getType())) {
-			String msg = "{0} must have type {1}, not: {2}"; //$NON-NLS-1$
-			msg = MessageFormat.format(msg, getClass().getSimpleName(), getType(), typeS);
-			throw new StrolchException(msg);
-		}
-
-		String interpretation = element.getAttribute(Tags.INTERPRETATION);
-		String hidden = element.getAttribute(Tags.HIDDEN);
-		String uom = element.getAttribute(Tags.UOM);
-		String index = element.getAttribute(Tags.INDEX);
-
-		setInterpretation(interpretation);
-		setUom(uom);
-
-		if (StringHelper.isEmpty(index)) {
-			this.index = 0;
-		} else {
-			this.index = Integer.valueOf(index);
-		}
-
-		if (StringHelper.isEmpty(hidden)) {
-			setHidden(false);
-		} else {
-			if (hidden.equalsIgnoreCase(Boolean.TRUE.toString())) {
-				setHidden(true);
-			} else if (hidden.equalsIgnoreCase(Boolean.FALSE.toString())) {
-				setHidden(false);
-			} else {
-				String msg = "Boolean string must be either {0} or {1}"; //$NON-NLS-1$
-				msg = MessageFormat.format(msg, Boolean.TRUE.toString(), Boolean.FALSE.toString());
-				throw new StrolchException(msg);
-			}
-		}
-	}
-
 	@Override
 	protected void fillLocator(LocatorBuilder lb) {
 		lb.append(Tags.STATE);
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timedstate/BooleanTimedState.java b/li.strolch.model/src/main/java/li/strolch/model/timedstate/BooleanTimedState.java
index 773421ff8..14c5aede4 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timedstate/BooleanTimedState.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timedstate/BooleanTimedState.java
@@ -15,19 +15,9 @@
  */
 package li.strolch.model.timedstate;
 
-import java.util.Date;
-import java.util.SortedSet;
-
-import li.strolch.model.Tags;
-import li.strolch.model.timevalue.ITimeValue;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.timevalue.impl.BooleanValue;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-import org.w3c.dom.NodeList;
-
-import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  */
@@ -35,8 +25,6 @@ public class BooleanTimedState extends AbstractStrolchTimedState<BooleanValue> {
 
 	private static final long serialVersionUID = 1L;
 
-	public static final String TYPE = "BooleanState";
-
 	public BooleanTimedState() {
 		super();
 	}
@@ -45,45 +33,14 @@ public class BooleanTimedState extends AbstractStrolchTimedState<BooleanValue> {
 		super(id, name);
 	}
 
-	public BooleanTimedState(Element element) {
-		super.fromDom(element);
-
-		this.state = new TimedState<>();
-
-		NodeList timeValueElems = element.getElementsByTagName(Tags.VALUE);
-		for (int i = 0; i < timeValueElems.getLength(); i++) {
-			Element timeValueElem = (Element) timeValueElems.item(i);
-			String timeS = timeValueElem.getAttribute(Tags.TIME);
-			Date date = ISO8601FormatFactory.getInstance().parseDate(timeS);
-			long time = date.getTime();
-
-			Boolean value = Boolean.valueOf(timeValueElem.getAttribute(Tags.VALUE));
-			BooleanValue booleanValue = new BooleanValue(value);
-			this.state.getTimeEvolution().setValueAt(time, booleanValue);
-		}
-	}
-
 	@Override
-	public Element toDom(Document doc) {
-
-		Element stateElement = doc.createElement(Tags.TIMED_STATE);
-		super.fillElement(stateElement);
-		SortedSet<ITimeValue<BooleanValue>> values = this.state.getTimeEvolution().getValues();
-		for (ITimeValue<BooleanValue> timeValue : values) {
-			Long time = timeValue.getTime();
-			BooleanValue value = timeValue.getValue();
-			Element valueElem = doc.createElement(Tags.VALUE);
-			valueElem.setAttribute(Tags.TIME, ISO8601FormatFactory.getInstance().formatDate(time));
-			valueElem.setAttribute(Tags.VALUE, value.getValue().toString());
-			stateElement.appendChild(valueElem);
-		}
-
-		return stateElement;
+	public void setStateFromStringAt(Long time, String value) {
+		getTimeEvolution().setValueAt(time, new BooleanValue(value));
 	}
 
 	@Override
 	public String getType() {
-		return TYPE;
+		return StrolchValueType.BOOLEAN.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timedstate/FloatTimedState.java b/li.strolch.model/src/main/java/li/strolch/model/timedstate/FloatTimedState.java
index bf1748cb8..a91918b91 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timedstate/FloatTimedState.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timedstate/FloatTimedState.java
@@ -15,19 +15,9 @@
  */
 package li.strolch.model.timedstate;
 
-import java.util.Date;
-import java.util.SortedSet;
-
-import li.strolch.model.Tags;
-import li.strolch.model.timevalue.ITimeValue;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.timevalue.impl.FloatValue;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-import org.w3c.dom.NodeList;
-
-import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  */
@@ -35,8 +25,6 @@ public class FloatTimedState extends AbstractStrolchTimedState<FloatValue> {
 
 	private static final long serialVersionUID = 1L;
 
-	public static final String TYPE = "FloatState";
-
 	public FloatTimedState() {
 		super();
 	}
@@ -45,45 +33,14 @@ public class FloatTimedState extends AbstractStrolchTimedState<FloatValue> {
 		super(id, name);
 	}
 
-	public FloatTimedState(Element element) {
-		super.fromDom(element);
-
-		this.state = new TimedState<>();
-
-		NodeList timeValueElems = element.getElementsByTagName(Tags.VALUE);
-		for (int i = 0; i < timeValueElems.getLength(); i++) {
-			Element timeValueElem = (Element) timeValueElems.item(i);
-			String timeS = timeValueElem.getAttribute(Tags.TIME);
-			Date date = ISO8601FormatFactory.getInstance().parseDate(timeS);
-			long time = date.getTime();
-
-			Double value = Double.valueOf(timeValueElem.getAttribute(Tags.VALUE));
-			FloatValue floatValue = new FloatValue(value);
-			this.state.getTimeEvolution().setValueAt(time, floatValue);
-		}
-	}
-
 	@Override
-	public Element toDom(Document doc) {
-
-		Element stateElement = doc.createElement(Tags.TIMED_STATE);
-		super.fillElement(stateElement);
-		SortedSet<ITimeValue<FloatValue>> values = this.state.getTimeEvolution().getValues();
-		for (ITimeValue<FloatValue> timeValue : values) {
-			Long time = timeValue.getTime();
-			FloatValue value = timeValue.getValue();
-			Element valueElem = doc.createElement(Tags.VALUE);
-			valueElem.setAttribute(Tags.TIME, ISO8601FormatFactory.getInstance().formatDate(time));
-			valueElem.setAttribute(Tags.VALUE, value.getValue().toString());
-			stateElement.appendChild(valueElem);
-		}
-
-		return stateElement;
+	public void setStateFromStringAt(Long time, String value) {
+		getTimeEvolution().setValueAt(time, new FloatValue(value));
 	}
 
 	@Override
 	public String getType() {
-		return TYPE;
+		return StrolchValueType.FLOAT.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timedstate/IntegerTimedState.java b/li.strolch.model/src/main/java/li/strolch/model/timedstate/IntegerTimedState.java
index dd239adad..63c39e46b 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timedstate/IntegerTimedState.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timedstate/IntegerTimedState.java
@@ -15,19 +15,9 @@
  */
 package li.strolch.model.timedstate;
 
-import java.util.Date;
-import java.util.SortedSet;
-
-import li.strolch.model.Tags;
-import li.strolch.model.timevalue.ITimeValue;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.timevalue.impl.IntegerValue;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-import org.w3c.dom.NodeList;
-
-import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  */
@@ -35,8 +25,6 @@ public class IntegerTimedState extends AbstractStrolchTimedState<IntegerValue> {
 
 	private static final long serialVersionUID = 1L;
 
-	public static final String TYPE = "IntegerState";
-
 	public IntegerTimedState() {
 		super();
 	}
@@ -45,45 +33,14 @@ public class IntegerTimedState extends AbstractStrolchTimedState<IntegerValue> {
 		super(id, name);
 	}
 
-	public IntegerTimedState(Element element) {
-		super.fromDom(element);
-
-		this.state = new TimedState<>();
-
-		NodeList timeValueElems = element.getElementsByTagName(Tags.VALUE);
-		for (int i = 0; i < timeValueElems.getLength(); i++) {
-			Element timeValueElem = (Element) timeValueElems.item(i);
-			String timeS = timeValueElem.getAttribute(Tags.TIME);
-			Date date = ISO8601FormatFactory.getInstance().parseDate(timeS);
-			long time = date.getTime();
-
-			Integer value = Integer.valueOf(timeValueElem.getAttribute(Tags.VALUE));
-			IntegerValue integerValue = new IntegerValue(value);
-			this.state.getTimeEvolution().setValueAt(time, integerValue);
-		}
-	}
-
 	@Override
-	public Element toDom(Document doc) {
-
-		Element stateElement = doc.createElement(Tags.TIMED_STATE);
-		super.fillElement(stateElement);
-		SortedSet<ITimeValue<IntegerValue>> values = this.state.getTimeEvolution().getValues();
-		for (ITimeValue<IntegerValue> timeValue : values) {
-			Long time = timeValue.getTime();
-			IntegerValue value = timeValue.getValue();
-			Element valueElem = doc.createElement(Tags.VALUE);
-			valueElem.setAttribute(Tags.TIME, ISO8601FormatFactory.getInstance().formatDate(time));
-			valueElem.setAttribute(Tags.VALUE, value.getValue().toString());
-			stateElement.appendChild(valueElem);
-		}
-
-		return stateElement;
+	public void setStateFromStringAt(Long time, String value) {
+		getTimeEvolution().setValueAt(time, new IntegerValue(value));
 	}
 
 	@Override
 	public String getType() {
-		return TYPE;
+		return StrolchValueType.INTEGER.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timedstate/StringSetTimedState.java b/li.strolch.model/src/main/java/li/strolch/model/timedstate/StringSetTimedState.java
index 72d7e6f10..9ebcfc3ca 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timedstate/StringSetTimedState.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timedstate/StringSetTimedState.java
@@ -15,23 +15,9 @@
  */
 package li.strolch.model.timedstate;
 
-import java.util.Date;
-import java.util.HashSet;
-import java.util.Iterator;
-import java.util.Set;
-import java.util.SortedSet;
-
-import li.strolch.model.Tags;
-import li.strolch.model.timevalue.ITimeValue;
-import li.strolch.model.timevalue.impl.AString;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.timevalue.impl.StringSetValue;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-import org.w3c.dom.NodeList;
-
-import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
-
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  */
@@ -39,8 +25,6 @@ public class StringSetTimedState extends AbstractStrolchTimedState<StringSetValu
 
 	private static final long serialVersionUID = 1L;
 
-	public static final String TYPE = "StringSetState";
-
 	public StringSetTimedState() {
 		super();
 	}
@@ -49,63 +33,14 @@ public class StringSetTimedState extends AbstractStrolchTimedState<StringSetValu
 		super(id, name);
 	}
 
-	public StringSetTimedState(Element element) {
-		super.fromDom(element);
-
-		this.state = new TimedState<>();
-
-		NodeList timeValueElems = element.getElementsByTagName(Tags.VALUE);
-		for (int i = 0; i < timeValueElems.getLength(); i++) {
-			Element timeValueElem = (Element) timeValueElems.item(i);
-			String timeS = timeValueElem.getAttribute(Tags.TIME);
-			Date date = ISO8601FormatFactory.getInstance().parseDate(timeS);
-			long time = date.getTime();
-
-			String valueAsString = timeValueElem.getAttribute(Tags.VALUE);
-			Set<AString> value = new HashSet<>();
-			String[] values = valueAsString.split(",");
-			for (String s : values) {
-				value.add(new AString(s.trim()));
-			}
-
-			StringSetValue integerValue = new StringSetValue(value);
-			this.state.getTimeEvolution().setValueAt(time, integerValue);
-		}
-	}
-
 	@Override
-	public Element toDom(Document doc) {
-
-		Element stateElement = doc.createElement(Tags.TIMED_STATE);
-		super.fillElement(stateElement);
-		SortedSet<ITimeValue<StringSetValue>> values = this.state.getTimeEvolution().getValues();
-		for (ITimeValue<StringSetValue> timeValue : values) {
-			Long time = timeValue.getTime();
-			StringSetValue stringSetValue = timeValue.getValue();
-
-			Set<AString> value = stringSetValue.getValue();
-			StringBuilder sb = new StringBuilder();
-			Iterator<AString> iter = value.iterator();
-			while (iter.hasNext()) {
-				sb.append(iter.next().getString());
-				if (iter.hasNext()) {
-					sb.append(", ");
-				}
-			}
-			String valueAsString = sb.toString();
-
-			Element valueElem = doc.createElement(Tags.VALUE);
-			valueElem.setAttribute(Tags.TIME, ISO8601FormatFactory.getInstance().formatDate(time));
-			valueElem.setAttribute(Tags.VALUE, valueAsString);
-			stateElement.appendChild(valueElem);
-		}
-
-		return stateElement;
+	public void setStateFromStringAt(Long time, String value) {
+		getTimeEvolution().setValueAt(time, new StringSetValue(value));
 	}
 
 	@Override
 	public String getType() {
-		return TYPE;
+		return StrolchValueType.STRING_SET.getType();
 	}
 
 	@Override
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timedstate/StrolchTimedState.java b/li.strolch.model/src/main/java/li/strolch/model/timedstate/StrolchTimedState.java
index 89ad1548a..76f8281e8 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timedstate/StrolchTimedState.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timedstate/StrolchTimedState.java
@@ -108,6 +108,16 @@ public interface StrolchTimedState<T extends IValue> extends StrolchElement {
 
 	public ITimeValue<T> getStateAt(Long time);
 
+	/**
+	 * set the value at a point in time to a given time value object from a string value
+	 *
+	 * @param time
+	 *            the time to set the {@link IValue}
+	 * @param value
+	 *            the string to parse to an {@link IValue}
+	 */
+	void setStateFromStringAt(final Long time, final String value);
+
 	public ITimeVariable<T> getTimeEvolution();
 
 	public void setParent(Resource aThis);
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timevalue/IValue.java b/li.strolch.model/src/main/java/li/strolch/model/timevalue/IValue.java
index 2c33a262d..53f8d02fe 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timevalue/IValue.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timevalue/IValue.java
@@ -26,6 +26,11 @@ package li.strolch.model.timevalue;
  */
 public interface IValue<T> {
 
+	/**
+	 * @return the type of this {@link IValue}
+	 */
+	String getType();
+
 	/**
 	 * @return the backing value
 	 */
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timevalue/IValueChange.java b/li.strolch.model/src/main/java/li/strolch/model/timevalue/IValueChange.java
index f9b880239..3dc923ac7 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timevalue/IValueChange.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timevalue/IValueChange.java
@@ -18,12 +18,9 @@ package li.strolch.model.timevalue;
 import li.strolch.model.timedstate.AbstractStrolchTimedState;
 import li.strolch.model.timevalue.impl.TimeVariable;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-
 /**
- * Interface for operators to be used to change the values of {@link ITimeValue}
- * in a {@link ITimeVariable} or {@link AbstractStrolchTimedState}.
+ * Interface for operators to be used to change the values of {@link ITimeValue} in a {@link ITimeVariable} or
+ * {@link AbstractStrolchTimedState}.
  * 
  * @author Martin Smock <smock.martin@gmail.com>
  */
@@ -31,15 +28,13 @@ import org.w3c.dom.Element;
 public interface IValueChange<T extends IValue> {
 
 	/**
-	 * @return the id of the {@link AbstractStrolchTimedState} the change
-	 *         applies to
+	 * @return the id of the {@link AbstractStrolchTimedState} the change applies to
 	 */
 	String getStateId();
 
 	/**
 	 * @param id
-	 *            the id of the {@link AbstractStrolchTimedState} the change
-	 *            applies to
+	 *            the id of the {@link AbstractStrolchTimedState} the change applies to
 	 */
 	void setStateId(String id);
 
@@ -47,31 +42,23 @@ public interface IValueChange<T extends IValue> {
 	 * @return the time this change has to be applied
 	 */
 	Long getTime();
-	
-	void setTime(Long time); 
+
+	void setTime(Long time);
 
 	/**
 	 * @return the value of the change
 	 */
 	T getValue();
-	
-	void setValue(T value); 
+
+	void setValue(T value);
 
 	/**
-	 * @return the inverse neutralizing a change. Very useful to undo changes
-	 *         made to a {@link TimeVariable}.
+	 * @return the inverse neutralizing a change. Very useful to undo changes made to a {@link TimeVariable}.
 	 */
 	IValueChange<T> getInverse();
-	
+
 	/**
 	 * @return a copy of this
 	 */
-	IValueChange<T> getClone(); 
-	
-	/**
-	 * @param doc
-	 * @return a xml serialisation of this
-	 */
-	Element toDom(Document doc); 
-
+	IValueChange<T> getClone();
 }
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/BooleanValue.java b/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/BooleanValue.java
index 4e00f603c..e66cdc998 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/BooleanValue.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/BooleanValue.java
@@ -17,6 +17,7 @@ package li.strolch.model.timevalue.impl;
 
 import java.io.Serializable;
 
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.timevalue.ITimeValue;
 import li.strolch.model.timevalue.IValue;
 
@@ -45,6 +46,11 @@ public class BooleanValue implements IValue<Boolean>, Serializable {
 		this.value = Boolean.parseBoolean(valueAsString);
 	}
 
+	@Override
+	public String getType() {
+		return StrolchValueType.BOOLEAN.getType();
+	}
+
 	@Override
 	public BooleanValue add(Boolean o) {
 		this.value = o;
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/FloatValue.java b/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/FloatValue.java
index deaddc02d..e1c059d4e 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/FloatValue.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/FloatValue.java
@@ -17,6 +17,7 @@ package li.strolch.model.timevalue.impl;
 
 import java.io.Serializable;
 
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.timevalue.ITimeValue;
 import li.strolch.model.timevalue.IValue;
 
@@ -53,6 +54,11 @@ public class FloatValue implements IValue<Double>, Serializable {
 		this.value = Double.parseDouble(valueAsString);
 	}
 
+	@Override
+	public String getType() {
+		return StrolchValueType.FLOAT.getType();
+	}
+
 	@Override
 	public FloatValue add(Double o) {
 		this.value += o;
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/IntegerValue.java b/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/IntegerValue.java
index c1476273f..2cf6f5b96 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/IntegerValue.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/IntegerValue.java
@@ -17,6 +17,7 @@ package li.strolch.model.timevalue.impl;
 
 import java.io.Serializable;
 
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.timevalue.ITimeValue;
 import li.strolch.model.timevalue.IValue;
 
@@ -45,6 +46,11 @@ public class IntegerValue implements IValue<Integer>, Serializable {
 		this.value = Integer.parseInt(valueAsString);
 	}
 
+	@Override
+	public String getType() {
+		return StrolchValueType.INTEGER.getType();
+	}
+
 	@Override
 	public IntegerValue add(Integer o) {
 		this.value += o;
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/StringSetValue.java b/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/StringSetValue.java
index e17c590c7..002298022 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/StringSetValue.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/StringSetValue.java
@@ -22,6 +22,7 @@ import java.util.Iterator;
 import java.util.Set;
 
 import li.strolch.exception.StrolchException;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.timevalue.ITimeValue;
 import li.strolch.model.timevalue.IValue;
 import ch.eitchnet.utils.dbc.DBC;
@@ -42,7 +43,7 @@ public class StringSetValue implements IValue<Set<AString>>, Serializable {
 
 	private Set<AString> aStrings = new HashSet<>();
 
-	public StringSetValue() {
+	private StringSetValue() {
 	}
 
 	public StringSetValue(final Set<AString> aStrings) {
@@ -50,6 +51,20 @@ public class StringSetValue implements IValue<Set<AString>>, Serializable {
 		this.aStrings = aStrings;
 	}
 
+	public StringSetValue(String valueAsString) {
+		Set<AString> value = new HashSet<>();
+		String[] values = valueAsString.split(",");
+		for (String s : values) {
+			value.add(new AString(s.trim()));
+		}
+		this.aStrings = value;
+	}
+
+	@Override
+	public String getType() {
+		return StrolchValueType.STRING_SET.getType();
+	}
+
 	@Override
 	public Set<AString> getValue() {
 		return this.aStrings;
diff --git a/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/ValueChange.java b/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/ValueChange.java
index db56b0936..ce8808558 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/ValueChange.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/timevalue/impl/ValueChange.java
@@ -17,15 +17,9 @@ package li.strolch.model.timevalue.impl;
 
 import java.io.Serializable;
 
-import li.strolch.model.Tags;
 import li.strolch.model.timevalue.IValue;
 import li.strolch.model.timevalue.IValueChange;
 
-import org.w3c.dom.Document;
-import org.w3c.dom.Element;
-
-import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
-
 /**
  * @author Martin Smock <smock.martin@gmail.com>
  */
@@ -67,7 +61,8 @@ public class ValueChange<T extends IValue> implements IValueChange<T>, Serializa
 	public Long getTime() {
 		return this.time;
 	}
-	
+
+	@Override
 	public void setTime(Long time) {
 		this.time = time;
 	}
@@ -77,7 +72,8 @@ public class ValueChange<T extends IValue> implements IValueChange<T>, Serializa
 	public T getValue() {
 		return (T) this.value.getCopy();
 	}
-	
+
+	@Override
 	public void setValue(T value) {
 		this.value = value;
 	}
@@ -134,13 +130,15 @@ public class ValueChange<T extends IValue> implements IValueChange<T>, Serializa
 		sb.append(this.time);
 		sb.append(", value=");
 		sb.append(this.value);
+		sb.append(", stateId=");
+		sb.append(this.stateId);
 		sb.append("]");
 		return sb.toString();
 	}
 
 	@Override
 	public String getStateId() {
-		return stateId;
+		return this.stateId;
 	}
 
 	@Override
@@ -151,17 +149,6 @@ public class ValueChange<T extends IValue> implements IValueChange<T>, Serializa
 	@SuppressWarnings("unchecked")
 	@Override
 	public IValueChange<T> getClone() {
-		return new ValueChange(time, value);
+		return new ValueChange(this.time, this.value, this.stateId);
 	}
-
-	@Override
-	public Element toDom(Document doc) {
-		Element element = doc.createElement(Tags.VALUE_CHANGE);
-		element.setAttribute(Tags.STATE_ID, this.stateId);
-		element.setAttribute(Tags.TIME, ISO8601FormatFactory.getInstance().formatDate(time));
-		element.setAttribute(Tags.VALUE, this.value.getValueAsString());
-		element.setAttribute(Tags.VALUE_CLASS, this.value.getClass().getName());
-		return element;
-	}
-
 }
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/AbstractToSaxWriterVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/AbstractToSaxWriterVisitor.java
index b71671ec8..c7423b850 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/xml/AbstractToSaxWriterVisitor.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/AbstractToSaxWriterVisitor.java
@@ -20,8 +20,9 @@ import static li.strolch.model.StrolchModelConstants.UOM_NONE;
 
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.Comparator;
+import java.util.Iterator;
 import java.util.List;
+import java.util.Map.Entry;
 import java.util.Set;
 import java.util.SortedSet;
 import java.util.TreeSet;
@@ -36,12 +37,15 @@ import li.strolch.model.ParameterizedElement;
 import li.strolch.model.Resource;
 import li.strolch.model.StrolchElement;
 import li.strolch.model.Tags;
+import li.strolch.model.activity.Action;
+import li.strolch.model.activity.Activity;
+import li.strolch.model.activity.IActivityElement;
 import li.strolch.model.parameter.Parameter;
 import li.strolch.model.timedstate.StrolchTimedState;
 import li.strolch.model.timevalue.ITimeValue;
 import li.strolch.model.timevalue.ITimeVariable;
 import li.strolch.model.timevalue.IValue;
-import ch.eitchnet.utils.helper.StringHelper;
+import li.strolch.model.timevalue.IValueChange;
 import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
 
 /**
@@ -55,16 +59,81 @@ public abstract class AbstractToSaxWriterVisitor {
 		this.writer = writer;
 	}
 
-	protected void writeElement(String tag, Order order) throws XMLStreamException {
+	protected void writeElement(Order order) throws XMLStreamException {
 		boolean empty = !order.hasParameterBags();
-		writeElement(tag, empty, order);
+
+		writeStartStrolchElement(Tags.ORDER, empty, order);
+		this.writer.writeAttribute(Tags.DATE, ISO8601FormatFactory.getInstance().formatDate(order.getDate()));
+		this.writer.writeAttribute(Tags.STATE, order.getState().name());
+
+		if (order.hasParameterBags()) {
+			writeParameterBags(order);
+		}
+
 		if (!empty)
 			this.writer.writeEndElement();
 	}
 
-	protected void writeElement(String tag, Resource resource) throws XMLStreamException {
+	protected void writeElement(Activity activity) throws XMLStreamException {
+		boolean empty = !activity.hasParameterBags() && !activity.hasElements();
+
+		writeStartStrolchElement(Tags.ACTIVITY, empty, activity);
+
+		if (activity.hasParameterBags()) {
+			writeParameterBags(activity);
+		}
+
+		if (activity.hasElements()) {
+			Iterator<Entry<String, IActivityElement>> iter = activity.elementIterator();
+			while (iter.hasNext()) {
+				IActivityElement element = iter.next().getValue();
+				if (element instanceof Activity)
+					writeElement((Activity) element);
+				else if (element instanceof Action)
+					writeElement((Action) element);
+				else
+					throw new IllegalArgumentException("Unhandled Element class " + element.getClass());
+			}
+		}
+
+		if (!empty)
+			this.writer.writeEndElement();
+	}
+
+	private <T> void writeElement(Action action) throws XMLStreamException {
+		boolean empty = !action.hasParameterBags() && !action.hasChanges();
+
+		writeStartStrolchElement(Tags.ACTION, empty, action);
+		this.writer.writeAttribute(Tags.STATE, action.getState().name());
+		this.writer.writeAttribute(Tags.RESOURCE_ID, action.getResourceId());
+		this.writer.writeAttribute(Tags.RESOURCE_TYPE, action.getResourceType());
+
+		if (action.hasParameterBags()) {
+			writeParameterBags(action);
+		}
+
+		if (action.hasChanges()) {
+			for (IValueChange<? extends IValue<?>> change : action.getChanges()) {
+				this.writer.writeEmptyElement(Tags.VALUE_CHANGE);
+				this.writer.writeAttribute(Tags.STATE_ID, change.getStateId());
+				this.writer.writeAttribute(Tags.TIME, ISO8601FormatFactory.getInstance().formatDate(change.getTime()));
+				this.writer.writeAttribute(Tags.VALUE, change.getValue().getValueAsString());
+				this.writer.writeAttribute(Tags.TYPE, change.getValue().getClass().getName());
+			}
+		}
+
+		if (!empty)
+			this.writer.writeEndElement();
+	}
+
+	protected void writeElement(Resource resource) throws XMLStreamException {
 		boolean empty = !resource.hasParameterBags() && !resource.hasTimedStates();
-		writeElement(tag, empty, resource);
+
+		writeStartStrolchElement(Tags.RESOURCE, empty, resource);
+
+		if (resource.hasParameterBags()) {
+			writeParameterBags(resource);
+		}
 
 		if (resource.hasTimedStates())
 			writeTimedStates(resource);
@@ -97,14 +166,6 @@ public abstract class AbstractToSaxWriterVisitor {
 		}
 	}
 
-	protected void writeElement(String tag, boolean empty, GroupedParameterizedElement element)
-			throws XMLStreamException {
-		writeStartStrolchElement(tag, empty, element);
-		if (!empty) {
-			writeParameterBags(element);
-		}
-	}
-
 	protected void writeStartStrolchElement(String tag, boolean empty, StrolchElement element)
 			throws XMLStreamException {
 		if (empty) {
@@ -114,9 +175,7 @@ public abstract class AbstractToSaxWriterVisitor {
 		}
 
 		this.writer.writeAttribute(Tags.ID, element.getId());
-		if (StringHelper.isNotEmpty(element.getName())) {
-			this.writer.writeAttribute(Tags.NAME, element.getName());
-		}
+		this.writer.writeAttribute(Tags.NAME, element.getName());
 		this.writer.writeAttribute(Tags.TYPE, element.getType());
 	}
 
@@ -136,12 +195,7 @@ public abstract class AbstractToSaxWriterVisitor {
 	protected void writeParameters(ParameterizedElement element) throws XMLStreamException {
 
 		List<Parameter<?>> parameters = new ArrayList<>(element.getParameters());
-		Collections.sort(parameters, new Comparator<Parameter<?>>() {
-			@Override
-			public int compare(Parameter<?> o1, Parameter<?> o2) {
-				return Integer.valueOf(o1.getIndex()).compareTo(o2.getIndex());
-			}
-		});
+		Collections.sort(parameters, (o1, o2) -> Integer.valueOf(o1.getIndex()).compareTo(o2.getIndex()));
 		for (Parameter<?> parameter : parameters) {
 			writeStartStrolchElement(Tags.PARAMETER, true, parameter);
 
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/ActivityToDomVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/ActivityToDomVisitor.java
new file mode 100644
index 000000000..9cbf8c231
--- /dev/null
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/ActivityToDomVisitor.java
@@ -0,0 +1,51 @@
+/*
+ * Copyright 2013 Robert von Burg <eitch@eitchnet.ch>
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package li.strolch.model.xml;
+
+import javax.xml.parsers.DocumentBuilder;
+
+import li.strolch.model.ActivityVisitor;
+import li.strolch.model.activity.Action;
+import li.strolch.model.activity.Activity;
+
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+
+import ch.eitchnet.utils.helper.DomUtil;
+
+/**
+ * @author Robert von Burg <eitch@eitchnet.ch>
+ */
+public class ActivityToDomVisitor extends StrolchElementToDomVisitor implements ActivityVisitor<Document> {
+
+	@Override
+	public Document visit(Activity activity) {
+		DocumentBuilder documentBuilder = DomUtil.createDocumentBuilder();
+		this.document = documentBuilder.getDOMImplementation().createDocument(null, null, null);
+
+		Element asDom = toDom(activity);
+		document.appendChild(asDom);
+		return this.document;
+	}
+
+	public Element toDom(Action action) {
+		return super.toDom(action);
+	}
+
+	public Element toDom(Activity activity) {
+		return super.toDom(activity);
+	}
+}
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/ActivityToSaxWriterVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/ActivityToSaxWriterVisitor.java
new file mode 100644
index 000000000..cc0a11204
--- /dev/null
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/ActivityToSaxWriterVisitor.java
@@ -0,0 +1,49 @@
+/*
+ * Copyright 2015 Robert von Burg <eitch@eitchnet.ch>
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package li.strolch.model.xml;
+
+import java.text.MessageFormat;
+
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamWriter;
+
+import li.strolch.exception.StrolchException;
+import li.strolch.model.ActivityVisitor;
+import li.strolch.model.activity.Activity;
+
+/**
+ * @author Robert von Burg <eitch@eitchnet.ch>
+ */
+public class ActivityToSaxWriterVisitor extends AbstractToSaxWriterVisitor implements ActivityVisitor<Void> {
+
+	public ActivityToSaxWriterVisitor(XMLStreamWriter writer) {
+		super(writer);
+	}
+
+	@Override
+	public Void visit(Activity activity) {
+		try {
+			writeElement(activity);
+			this.writer.flush();
+		} catch (XMLStreamException e) {
+			String msg = "Failed to write Activity {0} due to {1}"; //$NON-NLS-1$
+			msg = MessageFormat.format(msg, activity.getLocator(), e.getMessage());
+			throw new StrolchException(msg, e);
+		}
+
+		return null;
+	}
+}
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/OrderFromDomVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/OrderFromDomVisitor.java
new file mode 100644
index 000000000..a3b664fa4
--- /dev/null
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/OrderFromDomVisitor.java
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2015 Robert von Burg <eitch@eitchnet.ch>
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package li.strolch.model.xml;
+
+import li.strolch.model.Order;
+import li.strolch.model.State;
+import li.strolch.model.Tags;
+
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+
+import ch.eitchnet.utils.helper.StringHelper;
+import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
+
+/**
+ * @author Robert von Burg <eitch@eitchnet.ch>
+ */
+public class OrderFromDomVisitor extends StrolchElementFromDomVisitor {
+
+	public Order visit(Document doc) {
+		return fromDom(doc.getDocumentElement());
+	}
+
+	public Order fromDom(Element element) {
+		Order order = new Order();
+		fromDom(element, order);
+
+		String date = element.getAttribute(Tags.DATE);
+		String state = element.getAttribute(Tags.STATE);
+
+		if (StringHelper.isEmpty(date)) {
+			order.setDate(ISO8601FormatFactory.getInstance().getDateFormat().parse("-")); //$NON-NLS-1$
+		} else {
+			order.setDate(ISO8601FormatFactory.getInstance().getDateFormat().parse(date));
+		}
+
+		if (state == null || state.isEmpty()) {
+			order.setState(State.CREATED);
+		} else {
+			order.setState(State.valueOf(state));
+		}
+
+		return order;
+	}
+}
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/OrderToDomVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/OrderToDomVisitor.java
index 77c9995aa..07dc7829b 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/xml/OrderToDomVisitor.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/OrderToDomVisitor.java
@@ -28,25 +28,15 @@ import ch.eitchnet.utils.helper.DomUtil;
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  */
-public class OrderToDomVisitor implements OrderVisitor<Document> {
-
-	private Document document;
-
-	/**
-	 * @return the document
-	 */
-	public Document getDocument() {
-		return this.document;
-	}
+public class OrderToDomVisitor extends StrolchElementToDomVisitor implements OrderVisitor<Document> {
 
 	@Override
 	public Document visit(Order order) {
 		DocumentBuilder documentBuilder = DomUtil.createDocumentBuilder();
-		Document document = documentBuilder.getDOMImplementation().createDocument(null, null, null);
+		this.document = documentBuilder.getDOMImplementation().createDocument(null, null, null);
 
-		Element orderDom = order.toDom(document);
-		document.appendChild(orderDom);
-		this.document = document;
+		Element asDom = toDom(order);
+		document.appendChild(asDom);
 		return this.document;
 	}
 }
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/OrderToSaxWriterVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/OrderToSaxWriterVisitor.java
index dc3b16d52..ece6c6984 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/xml/OrderToSaxWriterVisitor.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/OrderToSaxWriterVisitor.java
@@ -23,7 +23,6 @@ import javax.xml.stream.XMLStreamWriter;
 import li.strolch.exception.StrolchException;
 import li.strolch.model.Order;
 import li.strolch.model.OrderVisitor;
-import li.strolch.model.Tags;
 
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
@@ -37,7 +36,7 @@ public class OrderToSaxWriterVisitor extends AbstractToSaxWriterVisitor implemen
 	@Override
 	public Void visit(Order order) {
 		try {
-			writeElement(Tags.ORDER, order);
+			writeElement(order);
 			this.writer.flush();
 		} catch (XMLStreamException e) {
 			String msg = "Failed to write Order {0} due to {1}"; //$NON-NLS-1$
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceFromDomVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceFromDomVisitor.java
new file mode 100644
index 000000000..d23773784
--- /dev/null
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceFromDomVisitor.java
@@ -0,0 +1,105 @@
+/*
+ * Copyright 2015 Robert von Burg <eitch@eitchnet.ch>
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package li.strolch.model.xml;
+
+import java.text.MessageFormat;
+import java.util.Date;
+
+import li.strolch.exception.StrolchException;
+import li.strolch.model.AbstractStrolchElement;
+import li.strolch.model.Resource;
+import li.strolch.model.StrolchValueType;
+import li.strolch.model.Tags;
+import li.strolch.model.timedstate.StrolchTimedState;
+import li.strolch.model.timevalue.IValue;
+
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+import org.w3c.dom.NodeList;
+
+import ch.eitchnet.utils.dbc.DBC;
+import ch.eitchnet.utils.helper.StringHelper;
+import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
+
+/**
+ * @author Robert von Burg <eitch@eitchnet.ch>
+ */
+public class ResourceFromDomVisitor extends StrolchElementFromDomVisitor {
+
+	public Resource visit(Document doc) {
+		return fromDom(doc.getDocumentElement());
+	}
+
+	public Resource fromDom(Element resourceElement) {
+		Resource resource = new Resource();
+		fromDom(resourceElement, resource);
+
+		NodeList timedStateElems = resourceElement.getElementsByTagName(Tags.TIMED_STATE);
+		for (int i = 0; i < timedStateElems.getLength(); i++) {
+			Element timedStateElem = (Element) timedStateElems.item(i);
+			String typeS = timedStateElem.getAttribute(Tags.TYPE);
+
+			DBC.PRE.assertNotEmpty("Type must be set on TimedState for resource with id " + resource.getId(), typeS);
+			StrolchValueType valueType = StrolchValueType.parse(typeS);
+			StrolchTimedState<? extends IValue<?>> timedState = valueType.timedStateInstance();
+
+			fromDom(timedStateElem, (AbstractStrolchElement) timedState);
+
+			String interpretation = timedStateElem.getAttribute(Tags.INTERPRETATION);
+			String hidden = timedStateElem.getAttribute(Tags.HIDDEN);
+			String uom = timedStateElem.getAttribute(Tags.UOM);
+			String index = timedStateElem.getAttribute(Tags.INDEX);
+
+			timedState.setInterpretation(interpretation);
+			timedState.setUom(uom);
+
+			if (StringHelper.isEmpty(index)) {
+				timedState.setIndex(0);
+			} else {
+				timedState.setIndex(Integer.valueOf(index));
+			}
+
+			if (StringHelper.isEmpty(hidden)) {
+				timedState.setHidden(false);
+			} else {
+				if (hidden.equalsIgnoreCase(Boolean.TRUE.toString())) {
+					timedState.setHidden(true);
+				} else if (hidden.equalsIgnoreCase(Boolean.FALSE.toString())) {
+					timedState.setHidden(false);
+				} else {
+					String msg = "Boolean string must be either {0} or {1}"; //$NON-NLS-1$
+					msg = MessageFormat.format(msg, Boolean.TRUE.toString(), Boolean.FALSE.toString());
+					throw new StrolchException(msg);
+				}
+			}
+
+			NodeList timeValueElems = timedStateElem.getElementsByTagName(Tags.VALUE);
+			for (int j = 0; j < timeValueElems.getLength(); j++) {
+				Element timeValueElem = (Element) timeValueElems.item(j);
+				String timeS = timeValueElem.getAttribute(Tags.TIME);
+				Date date = ISO8601FormatFactory.getInstance().parseDate(timeS);
+				long time = date.getTime();
+
+				String valueS = timeValueElem.getAttribute(Tags.VALUE);
+				timedState.setStateFromStringAt(time, valueS);
+			}
+
+			resource.addTimedState(timedState);
+		}
+
+		return resource;
+	}
+}
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceToDomVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceToDomVisitor.java
index 2942d547c..e783bcfc1 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceToDomVisitor.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceToDomVisitor.java
@@ -28,25 +28,15 @@ import ch.eitchnet.utils.helper.DomUtil;
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
  */
-public class ResourceToDomVisitor implements ResourceVisitor<Document> {
-
-	private Document document;
-
-	/**
-	 * @return the document
-	 */
-	public Document getDocument() {
-		return this.document;
-	}
+public class ResourceToDomVisitor extends StrolchElementToDomVisitor implements ResourceVisitor<Document> {
 
 	@Override
 	public Document visit(Resource resource) {
 		DocumentBuilder documentBuilder = DomUtil.createDocumentBuilder();
-		Document document = documentBuilder.getDOMImplementation().createDocument(null, null, null);
+		this.document = documentBuilder.getDOMImplementation().createDocument(null, null, null);
 
-		Element resourceDom = resource.toDom(document);
-		document.appendChild(resourceDom);
-		this.document = document;
+		Element asDom = toDom(resource);
+		document.appendChild(asDom);
 		return this.document;
 	}
 }
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceToSaxWriterVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceToSaxWriterVisitor.java
index 764984a14..3b64c4b04 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceToSaxWriterVisitor.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/ResourceToSaxWriterVisitor.java
@@ -23,7 +23,6 @@ import javax.xml.stream.XMLStreamWriter;
 import li.strolch.exception.StrolchException;
 import li.strolch.model.Resource;
 import li.strolch.model.ResourceVisitor;
-import li.strolch.model.Tags;
 
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
@@ -37,7 +36,7 @@ public class ResourceToSaxWriterVisitor extends AbstractToSaxWriterVisitor imple
 	@Override
 	public Void visit(Resource resource) {
 		try {
-			writeElement(Tags.RESOURCE, resource);
+			writeElement(resource);
 			this.writer.flush();
 		} catch (XMLStreamException e) {
 			String msg = "Failed to write Resource {0} due to {1}"; //$NON-NLS-1$
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/StrolchElementFromDomVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/StrolchElementFromDomVisitor.java
new file mode 100644
index 000000000..986748cf5
--- /dev/null
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/StrolchElementFromDomVisitor.java
@@ -0,0 +1,122 @@
+/*
+ * Copyright 2015 Robert von Burg <eitch@eitchnet.ch>
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package li.strolch.model.xml;
+
+import java.text.MessageFormat;
+
+import li.strolch.exception.StrolchException;
+import li.strolch.model.AbstractStrolchElement;
+import li.strolch.model.GroupedParameterizedElement;
+import li.strolch.model.ParameterBag;
+import li.strolch.model.ParameterizedElement;
+import li.strolch.model.StrolchValueType;
+import li.strolch.model.Tags;
+import li.strolch.model.parameter.Parameter;
+
+import org.w3c.dom.Element;
+import org.w3c.dom.NodeList;
+
+import ch.eitchnet.utils.helper.StringHelper;
+
+/**
+ * @author Robert von Burg <eitch@eitchnet.ch>
+ */
+public class StrolchElementFromDomVisitor {
+
+	protected void fromDom(Element element, AbstractStrolchElement strolchElement) {
+		String id = element.getAttribute(Tags.ID);
+		String name = element.getAttribute(Tags.NAME);
+
+		if (id != null && name != null) {
+			strolchElement.setId(id);
+			strolchElement.setName(name);
+		} else {
+			String msg = "Check the values of the element: {0} either id or name attribute is null!"; //$NON-NLS-1$
+			msg = MessageFormat.format(msg, element.getNodeName());
+			throw new StrolchException(msg);
+		}
+	}
+
+	protected void fromDom(Element element, GroupedParameterizedElement order) {
+		fromDom(element, (AbstractStrolchElement) order);
+
+		String type = element.getAttribute(Tags.TYPE);
+		order.setType(type);
+
+		NodeList bags = element.getElementsByTagName(Tags.PARAMETER_BAG);
+		for (int i = 0; i < bags.getLength(); i++) {
+			Element bagElement = (Element) bags.item(i);
+			ParameterBag bag = new ParameterBag();
+			fromDom(bagElement, bag);
+			order.addParameterBag(bag);
+		}
+	}
+
+	protected void fromDom(Element element, ParameterizedElement parameterizedElement) {
+		fromDom(element, (AbstractStrolchElement) parameterizedElement);
+
+		String type = element.getAttribute(Tags.TYPE);
+		parameterizedElement.setType(type);
+
+		// add all the parameters
+		NodeList parameterElements = element.getElementsByTagName(Tags.PARAMETER);
+		for (int i = 0; i < parameterElements.getLength(); i++) {
+			Element paramElement = (Element) parameterElements.item(i);
+			String paramtype = paramElement.getAttribute(Tags.TYPE);
+
+			StrolchValueType paramValueType = StrolchValueType.parse(paramtype);
+			Parameter<?> parameter = paramValueType.parameterInstance();
+			fromDom(paramElement, parameter);
+			parameterizedElement.addParameter(parameter);
+		}
+	}
+
+	protected void fromDom(Element element, Parameter<?> param) {
+
+		fromDom(element, (AbstractStrolchElement) param);
+
+		String value = element.getAttribute(Tags.VALUE);
+		param.setValueFromString(value);
+
+		String interpretation = element.getAttribute(Tags.INTERPRETATION);
+		String hidden = element.getAttribute(Tags.HIDDEN);
+		String uom = element.getAttribute(Tags.UOM);
+		String index = element.getAttribute(Tags.INDEX);
+
+		param.setInterpretation(interpretation);
+		param.setUom(uom);
+
+		if (StringHelper.isEmpty(index)) {
+			param.setIndex(0);
+		} else {
+			param.setIndex(Integer.valueOf(index));
+		}
+
+		if (StringHelper.isEmpty(hidden)) {
+			param.setHidden(false);
+		} else {
+			if (hidden.equalsIgnoreCase(Boolean.TRUE.toString())) {
+				param.setHidden(true);
+			} else if (hidden.equalsIgnoreCase(Boolean.FALSE.toString())) {
+				param.setHidden(false);
+			} else {
+				String msg = "Boolean string must be either {0} or {1}"; //$NON-NLS-1$
+				msg = MessageFormat.format(msg, Boolean.TRUE.toString(), Boolean.FALSE.toString());
+				throw new StrolchException(msg);
+			}
+		}
+	}
+}
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/StrolchElementToDomVisitor.java b/li.strolch.model/src/main/java/li/strolch/model/xml/StrolchElementToDomVisitor.java
new file mode 100644
index 000000000..5a00f1a3b
--- /dev/null
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/StrolchElementToDomVisitor.java
@@ -0,0 +1,222 @@
+/*
+ * Copyright 2015 Robert von Burg <eitch@eitchnet.ch>
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package li.strolch.model.xml;
+
+import java.util.Iterator;
+import java.util.Map.Entry;
+import java.util.SortedSet;
+
+import li.strolch.model.AbstractStrolchElement;
+import li.strolch.model.GroupedParameterizedElement;
+import li.strolch.model.Order;
+import li.strolch.model.ParameterBag;
+import li.strolch.model.ParameterizedElement;
+import li.strolch.model.Resource;
+import li.strolch.model.StrolchModelConstants;
+import li.strolch.model.Tags;
+import li.strolch.model.activity.Action;
+import li.strolch.model.activity.Activity;
+import li.strolch.model.activity.IActivityElement;
+import li.strolch.model.parameter.Parameter;
+import li.strolch.model.timedstate.StrolchTimedState;
+import li.strolch.model.timevalue.ITimeValue;
+import li.strolch.model.timevalue.IValue;
+import li.strolch.model.timevalue.IValueChange;
+
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+
+import ch.eitchnet.utils.iso8601.ISO8601FormatFactory;
+
+/**
+ * @author Robert von Burg <eitch@eitchnet.ch>
+ */
+public class StrolchElementToDomVisitor {
+
+	protected Document document;
+
+	public Document getDocument() {
+		return this.document;
+	}
+
+	protected Element toDom(Order order) {
+
+		Element asDom = document.createElement(Tags.ORDER);
+		fillElement(asDom, order);
+
+		asDom.setAttribute(Tags.DATE, ISO8601FormatFactory.getInstance().formatDate(order.getDate()));
+		asDom.setAttribute(Tags.STATE, order.getState().name());
+
+		return asDom;
+	}
+
+	protected Element toDom(Resource resource) {
+
+		Element asDom = document.createElement(Tags.RESOURCE);
+		fillElement(asDom, resource);
+
+		if (resource.hasTimedStates()) {
+			for (String stateKey : resource.getTimedStateKeySet()) {
+				StrolchTimedState<IValue<?>> timedState = resource.getTimedState(stateKey);
+				Element stateElement = toDom(timedState);
+				asDom.appendChild(stateElement);
+			}
+		}
+
+		return asDom;
+	}
+
+	protected Element toDom(Activity activity) {
+		Element element = document.createElement(Tags.ACTIVITY);
+		fillElement(element, activity);
+
+		if (activity.hasElements()) {
+			Iterator<Entry<String, IActivityElement>> iter = activity.elementIterator();
+			while (iter.hasNext()) {
+				IActivityElement activityElement = iter.next().getValue();
+				if (activityElement instanceof Activity) {
+					element.appendChild(toDom((Activity) activityElement));
+				} else if (activityElement instanceof Action) {
+					element.appendChild(toDom((Action) activityElement));
+				}
+			}
+		}
+
+		return element;
+	}
+
+	protected Element toDom(Action action) {
+		Element element = document.createElement(Tags.ACTION);
+		fillElement(element, action);
+
+		element.setAttribute(Tags.RESOURCE_ID, action.getResourceId());
+		element.setAttribute(Tags.RESOURCE_TYPE, action.getResourceType());
+		element.setAttribute(Tags.STATE, action.getState().name());
+
+		if (action.hasChanges()) {
+			Iterator<IValueChange<? extends IValue<?>>> iter = action.changesIterator();
+			while (iter.hasNext()) {
+				IValueChange<? extends IValue<?>> value = iter.next();
+				Element valueChangeElement = toDom(value);
+				element.appendChild(valueChangeElement);
+			}
+		}
+
+		return element;
+	}
+
+	protected Element toDom(IValueChange<? extends IValue<?>> value) {
+		Element element = document.createElement(Tags.VALUE_CHANGE);
+		element.setAttribute(Tags.STATE_ID, value.getStateId());
+		element.setAttribute(Tags.TIME, ISO8601FormatFactory.getInstance().formatDate(value.getTime()));
+		element.setAttribute(Tags.VALUE, value.getValue().getValueAsString());
+		element.setAttribute(Tags.TYPE, value.getValue().getType());
+		return element;
+	}
+
+	protected Element toDom(StrolchTimedState<IValue<?>> timedState) {
+
+		Element element = document.createElement(Tags.TIMED_STATE);
+		fillElement(element, (AbstractStrolchElement) timedState);
+
+		if (!timedState.getInterpretation().equals(StrolchModelConstants.INTERPRETATION_NONE)) {
+			element.setAttribute(Tags.INTERPRETATION, timedState.getInterpretation());
+		}
+		if (!timedState.getUom().equals(StrolchModelConstants.UOM_NONE)) {
+			element.setAttribute(Tags.UOM, timedState.getUom());
+		}
+		if (timedState.isHidden()) {
+			element.setAttribute(Tags.HIDDEN, Boolean.toString(timedState.isHidden()));
+		}
+		if (timedState.getIndex() != 0) {
+			element.setAttribute(Tags.INDEX, Integer.toString(timedState.getIndex()));
+		}
+
+		SortedSet<ITimeValue<IValue<?>>> values = timedState.getTimeEvolution().getValues();
+		for (ITimeValue<IValue<?>> iTimeValue : values) {
+
+			Long time = iTimeValue.getTime();
+			String valueS = iTimeValue.getValue().getValueAsString();
+
+			Element valueElement = document.createElement(Tags.VALUE);
+			valueElement.setAttribute(Tags.TIME, ISO8601FormatFactory.getInstance().formatDate(time));
+			valueElement.setAttribute(Tags.VALUE, valueS);
+
+			element.appendChild(valueElement);
+		}
+
+		return element;
+	}
+
+	protected Element toDom(ParameterBag bag) {
+		Element bagElement = document.createElement(Tags.PARAMETER_BAG);
+		fillElement(bagElement, (ParameterizedElement) bag);
+		return bagElement;
+	}
+
+	protected Element toDom(Parameter<?> param) {
+		Element element = document.createElement(Tags.PARAMETER);
+		fillElement(element, (AbstractStrolchElement) param);
+
+		element.setAttribute(Tags.VALUE, param.getValueAsString());
+
+		if (!param.getInterpretation().equals(StrolchModelConstants.INTERPRETATION_NONE)) {
+			element.setAttribute(Tags.INTERPRETATION, param.getInterpretation());
+		}
+		if (!param.getUom().equals(StrolchModelConstants.UOM_NONE)) {
+			element.setAttribute(Tags.UOM, param.getUom());
+		}
+		if (param.isHidden()) {
+			element.setAttribute(Tags.HIDDEN, Boolean.toString(param.isHidden()));
+		}
+		if (param.getIndex() != 0) {
+			element.setAttribute(Tags.INDEX, Integer.toString(param.getIndex()));
+		}
+
+		return element;
+	}
+
+	protected void fillElement(Element element, AbstractStrolchElement strolchElement) {
+		element.setAttribute(Tags.ID, strolchElement.getId());
+		element.setAttribute(Tags.NAME, strolchElement.getName());
+		element.setAttribute(Tags.TYPE, strolchElement.getType());
+	}
+
+	protected void fillElement(Element element, GroupedParameterizedElement groupedParameterizedElement) {
+		fillElement(element, (AbstractStrolchElement) groupedParameterizedElement);
+
+		if (groupedParameterizedElement.hasParameterBags()) {
+			for (String bagKey : groupedParameterizedElement.getParameterBagKeySet()) {
+				ParameterBag bag = groupedParameterizedElement.getParameterBag(bagKey);
+				Element bagElement = toDom(bag);
+				element.appendChild(bagElement);
+			}
+		}
+	}
+
+	protected void fillElement(Element element, ParameterizedElement parameterizedElement) {
+		fillElement(element, (AbstractStrolchElement) parameterizedElement);
+
+		if (parameterizedElement.hasParameters()) {
+			for (String paramKey : parameterizedElement.getParameterKeySet()) {
+				Parameter<?> parameter = parameterizedElement.getParameter(paramKey);
+				Element paramElement = toDom(parameter);
+				element.appendChild(paramElement);
+			}
+		}
+	}
+
+}
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/XmlModelSaxFileReader.java b/li.strolch.model/src/main/java/li/strolch/model/xml/XmlModelSaxFileReader.java
index d805274f8..1c2d9be32 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/xml/XmlModelSaxFileReader.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/XmlModelSaxFileReader.java
@@ -76,8 +76,7 @@ public class XmlModelSaxFileReader extends XmlModelSaxReader {
 
 			XmlModelSaxFileReader handler = new XmlModelSaxFileReader(this.listener, includeFile, this.allowInclude);
 			handler.parseFile();
-			this.statistics.nrOfOrders += handler.statistics.nrOfOrders;
-			this.statistics.nrOfResources += handler.statistics.nrOfResources;
+			this.statistics.add(handler.statistics);
 
 			break;
 		default:
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/XmlModelSaxReader.java b/li.strolch.model/src/main/java/li/strolch/model/xml/XmlModelSaxReader.java
index e97751b15..4c29a79f6 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/xml/XmlModelSaxReader.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/XmlModelSaxReader.java
@@ -16,9 +16,9 @@
 package li.strolch.model.xml;
 
 import java.text.MessageFormat;
+import java.util.ArrayDeque;
 import java.util.Date;
-import java.util.HashSet;
-import java.util.Set;
+import java.util.Deque;
 
 import li.strolch.exception.StrolchException;
 import li.strolch.model.GroupedParameterizedElement;
@@ -27,30 +27,14 @@ import li.strolch.model.Order;
 import li.strolch.model.ParameterBag;
 import li.strolch.model.Resource;
 import li.strolch.model.State;
+import li.strolch.model.StrolchValueType;
 import li.strolch.model.Tags;
-import li.strolch.model.parameter.BooleanParameter;
-import li.strolch.model.parameter.DateParameter;
-import li.strolch.model.parameter.DurationParameter;
-import li.strolch.model.parameter.FloatListParameter;
-import li.strolch.model.parameter.FloatParameter;
-import li.strolch.model.parameter.IntegerListParameter;
-import li.strolch.model.parameter.IntegerParameter;
-import li.strolch.model.parameter.LongListParameter;
-import li.strolch.model.parameter.LongParameter;
+import li.strolch.model.activity.Action;
+import li.strolch.model.activity.Activity;
 import li.strolch.model.parameter.Parameter;
-import li.strolch.model.parameter.StringListParameter;
-import li.strolch.model.parameter.StringParameter;
-import li.strolch.model.timedstate.BooleanTimedState;
-import li.strolch.model.timedstate.FloatTimedState;
-import li.strolch.model.timedstate.IntegerTimedState;
-import li.strolch.model.timedstate.StringSetTimedState;
 import li.strolch.model.timedstate.StrolchTimedState;
 import li.strolch.model.timevalue.IValue;
-import li.strolch.model.timevalue.impl.AString;
-import li.strolch.model.timevalue.impl.BooleanValue;
-import li.strolch.model.timevalue.impl.FloatValue;
-import li.strolch.model.timevalue.impl.IntegerValue;
-import li.strolch.model.timevalue.impl.StringSetValue;
+import li.strolch.model.timevalue.impl.ValueChange;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -72,13 +56,15 @@ public class XmlModelSaxReader extends DefaultHandler {
 	protected ModelStatistics statistics;
 
 	private GroupedParameterizedElement parameterizedElement;
+	private Deque<Activity> activityStack;
 	private ParameterBag pBag;
 	private StrolchTimedState<? extends IValue<?>> state;
-	private String stateType;
+	private StrolchValueType stateType;
 
 	public XmlModelSaxReader(StrolchElementListener listener) {
 		this.listener = listener;
 		this.statistics = new ModelStatistics();
+		this.activityStack = new ArrayDeque<>();
 	}
 
 	/**
@@ -104,6 +90,56 @@ public class XmlModelSaxReader extends DefaultHandler {
 			String resType = attributes.getValue(Tags.TYPE);
 			Resource resource = new Resource(resId, resName, resType);
 			this.parameterizedElement = resource;
+
+			break;
+
+		case Tags.ACTIVITY:
+
+			String activityId = attributes.getValue(Tags.ID);
+			String activityName = attributes.getValue(Tags.NAME);
+			String activityType = attributes.getValue(Tags.TYPE);
+			Activity activity = new Activity(activityId, activityName, activityType);
+			this.parameterizedElement = activity;
+			this.activityStack.push(activity);
+
+			break;
+
+		case Tags.ACTION:
+
+			// Action Id="action_1" Name="Action 1" ResourceId="dummyId" ResourceType="dummyType" State="CREATED" Type="Use"
+
+			String actionId = attributes.getValue(Tags.ID);
+			String actionName = attributes.getValue(Tags.NAME);
+			String actionType = attributes.getValue(Tags.TYPE);
+			String actionResourceId = attributes.getValue(Tags.RESOURCE_ID);
+			String actionResourceType = attributes.getValue(Tags.RESOURCE_TYPE);
+			String actionState = attributes.getValue(Tags.STATE);
+			Action action = new Action(actionId, actionName, actionType);
+			action.setResourceId(actionResourceId);
+			action.setResourceType(actionResourceType);
+			action.setState(State.valueOf(actionState));
+
+			this.activityStack.peek().addElement(action);
+			this.parameterizedElement = action;
+
+			break;
+
+		case Tags.VALUE_CHANGE:
+
+			// ValueChange StateId="dummyId" Time="2012-11-30T18:12:05.628+01:00" Value="5" ValueClass="Integer"
+
+			String valueChangeStateId = attributes.getValue(Tags.STATE_ID);
+			String valueChangeTimeS = attributes.getValue(Tags.TIME);
+			String valueChangeValue = attributes.getValue(Tags.VALUE);
+			String valueChangeType = attributes.getValue(Tags.TYPE);
+
+			IValue<?> value = StrolchValueType.parse(valueChangeType).valueInstance(valueChangeValue);
+			long valueChangeTime = ISO8601FormatFactory.getInstance().getDateFormat().parse(valueChangeTimeS).getTime();
+			ValueChange<IValue<?>> valueChange = new ValueChange<IValue<?>>(valueChangeTime, value);
+			valueChange.setStateId(valueChangeStateId);
+
+			((Action) this.parameterizedElement).addChange(valueChange);
+
 			break;
 
 		case Tags.ORDER:
@@ -122,6 +158,7 @@ public class XmlModelSaxReader extends DefaultHandler {
 				order.setState(orderState);
 			}
 			this.parameterizedElement = order;
+
 			break;
 
 		case Tags.PARAMETER_BAG:
@@ -131,12 +168,11 @@ public class XmlModelSaxReader extends DefaultHandler {
 			ParameterBag pBag = new ParameterBag(pBagId, pBagName, pBagType);
 			this.pBag = pBag;
 			this.parameterizedElement.addParameterBag(pBag);
+
 			break;
 
 		case Tags.PARAMETER:
 
-			// TODO refactor this code into using visitors
-
 			String paramId = attributes.getValue(Tags.ID);
 			String paramName = attributes.getValue(Tags.NAME);
 			String paramType = attributes.getValue(Tags.TYPE);
@@ -149,110 +185,50 @@ public class XmlModelSaxReader extends DefaultHandler {
 						.parseBoolean(paramHiddenS);
 				String paramUom = attributes.getValue(Tags.UOM);
 				String paramInterpretation = attributes.getValue(Tags.INTERPRETATION);
-				Parameter<?> param;
-				switch (paramType) {
-				case StringParameter.TYPE:
-					param = new StringParameter(paramId, paramName, paramValue);
-					break;
-				case IntegerParameter.TYPE:
-					param = new IntegerParameter(paramId, paramName, IntegerParameter.parseFromString(paramValue));
-					break;
-				case BooleanParameter.TYPE:
-					param = new BooleanParameter(paramId, paramName, BooleanParameter.parseFromString(paramValue));
-					break;
-				case LongParameter.TYPE:
-					param = new LongParameter(paramId, paramName, LongParameter.parseFromString(paramValue));
-					break;
-				case DateParameter.TYPE:
-					param = new DateParameter(paramId, paramName, DateParameter.parseFromString(paramValue));
-					break;
-				case DurationParameter.TYPE:
-					param = new DurationParameter(paramId, paramName, DurationParameter.parseFromString(paramValue));
-					break;
-				case StringListParameter.TYPE:
-					param = new StringListParameter(paramId, paramName, StringListParameter.parseFromString(paramValue));
-					break;
-				case IntegerListParameter.TYPE:
-					param = new IntegerListParameter(paramId, paramName,
-							IntegerListParameter.parseFromString(paramValue));
-					break;
-				case FloatListParameter.TYPE:
-					param = new FloatListParameter(paramId, paramName, FloatListParameter.parseFromString(paramValue));
-					break;
-				case LongListParameter.TYPE:
-					param = new LongListParameter(paramId, paramName, LongListParameter.parseFromString(paramValue));
-					break;
-				case FloatParameter.TYPE:
-					param = new FloatParameter(paramId, paramName, FloatParameter.parseFromString(paramValue));
-					break;
-				default:
-					throw new UnsupportedOperationException(MessageFormat.format(
-							"Parameters of type {0} are not supported!", paramType)); //$NON-NLS-1$
-				}
+
+				StrolchValueType type = StrolchValueType.parse(paramType);
+
+				Parameter<?> param = type.parameterInstance();
+				param.setId(paramId);
+				param.setName(paramName);
+				param.setValueFromString(paramValue);
+
 				param.setHidden(paramHidden);
 				param.setUom(paramUom);
 				param.setInterpretation(paramInterpretation);
 				param.setIndex(index);
+
 				this.pBag.addParameter(param);
+
 			} catch (Exception e) {
 				throw new StrolchException("Failed to instantiate parameter " + paramId + " for bag "
 						+ this.pBag.getLocator() + " due to " + e.getMessage(), e);
 			}
+
 			break;
 
 		case Tags.TIMED_STATE:
+
 			String stateId = attributes.getValue(Tags.ID);
 			String stateName = attributes.getValue(Tags.NAME);
-			this.stateType = attributes.getValue(Tags.TYPE);
+			String stateType = attributes.getValue(Tags.TYPE);
 
-			switch (this.stateType) {
-			case FloatTimedState.TYPE:
-				this.state = new FloatTimedState(stateId, stateName);
-				break;
-			case IntegerTimedState.TYPE:
-				this.state = new IntegerTimedState(stateId, stateName);
-				break;
-			case BooleanTimedState.TYPE:
-				this.state = new BooleanTimedState(stateId, stateName);
-				break;
-			case StringSetTimedState.TYPE:
-				this.state = new StringSetTimedState(stateId, stateName);
-				break;
-			default:
-				break;
-			}
+			this.stateType = StrolchValueType.parse(stateType);
+			this.state = this.stateType.timedStateInstance();
+			this.state.setId(stateId);
+			this.state.setName(stateName);
 
 			break;
 
 		case Tags.VALUE:
+
 			String valueTime = attributes.getValue(Tags.TIME);
 			Date date = ISO8601FormatFactory.getInstance().parseDate(valueTime);
 			long time = date.getTime();
 			String valueValue = attributes.getValue(Tags.VALUE);
-			switch (this.stateType) {
-			case FloatTimedState.TYPE:
-				((FloatTimedState) this.state).getTimeEvolution().setValueAt(time, new FloatValue(valueValue));
-				break;
-			case IntegerTimedState.TYPE:
-				((IntegerTimedState) this.state).getTimeEvolution().setValueAt(time, new IntegerValue(valueValue));
-				break;
-			case BooleanTimedState.TYPE:
-				((BooleanTimedState) this.state).getTimeEvolution().setValueAt(time, new BooleanValue(valueValue));
-				break;
-			case StringSetTimedState.TYPE:
 
-				Set<AString> value = new HashSet<>();
-				String[] values = valueValue.split(",");
-				for (String s : values) {
-					value.add(new AString(s.trim()));
-				}
+			this.state.setStateFromStringAt(time, valueValue);
 
-				StringSetValue stringSetValue = new StringSetValue(value);
-				((StringSetTimedState) this.state).getTimeEvolution().setValueAt(time, stringSetValue);
-				break;
-			default:
-				break;
-			}
 			break;
 
 		default:
@@ -264,30 +240,58 @@ public class XmlModelSaxReader extends DefaultHandler {
 	public void endElement(String uri, String localName, String qName) throws SAXException {
 
 		switch (qName) {
-		case Tags.STROLCH_MODEL:
-			break;
 		case Tags.RESOURCE:
 			this.listener.notifyResource((Resource) this.parameterizedElement);
 			this.statistics.nrOfResources++;
 			this.parameterizedElement = null;
+
 			break;
+
+		case Tags.ACTIVITY:
+
+			Activity activity = this.activityStack.pop();
+			if (this.activityStack.isEmpty()) {
+				this.listener.notifyActivity(activity);
+				this.statistics.nrOfActivities++;
+			}
+			this.parameterizedElement = null;
+
+			break;
+
 		case Tags.ORDER:
+
 			this.listener.notifyOrder((Order) this.parameterizedElement);
 			this.statistics.nrOfOrders++;
 			this.parameterizedElement = null;
+
 			break;
+
+		case Tags.ACTION:
+
+			this.parameterizedElement = null;
+
+			break;
+
 		case Tags.PARAMETER_BAG:
+
 			this.pBag = null;
+
 			break;
-		case Tags.PARAMETER:
-			break;
-		case Tags.INCLUDE_FILE:
-			break;
+
 		case Tags.TIMED_STATE:
+
 			((Resource) this.parameterizedElement).addTimedState(this.state);
+
 			break;
+
+		case Tags.PARAMETER:
+		case Tags.INCLUDE_FILE:
 		case Tags.VALUE:
+		case Tags.VALUE_CHANGE:
+		case Tags.STROLCH_MODEL:
+
 			break;
+
 		default:
 			throw new IllegalArgumentException(MessageFormat.format("The element ''{0}'' is unhandled!", qName)); //$NON-NLS-1$
 		}
diff --git a/li.strolch.model/src/test/java/li/strolch/model/ModelTest.java b/li.strolch.model/src/test/java/li/strolch/model/ModelTest.java
index 777a8a6dd..98acd84d8 100644
--- a/li.strolch.model/src/test/java/li/strolch/model/ModelTest.java
+++ b/li.strolch.model/src/test/java/li/strolch/model/ModelTest.java
@@ -86,10 +86,14 @@ import li.strolch.model.visitor.OrderDeepEqualsVisitor;
 import li.strolch.model.visitor.ResourceDeepEqualsVisitor;
 
 import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 @SuppressWarnings("nls")
 public class ModelTest {
 
+	protected static final Logger logger = LoggerFactory.getLogger(ModelTest.class);
+
 	@Test
 	public void shouldCreateResource() {
 
diff --git a/li.strolch.model/src/test/java/li/strolch/model/XmlToDomTest.java b/li.strolch.model/src/test/java/li/strolch/model/XmlToDomTest.java
index 84f3438f0..8d66c911b 100644
--- a/li.strolch.model/src/test/java/li/strolch/model/XmlToDomTest.java
+++ b/li.strolch.model/src/test/java/li/strolch/model/XmlToDomTest.java
@@ -18,12 +18,13 @@ package li.strolch.model;
 import static org.junit.Assert.assertTrue;
 import li.strolch.model.visitor.OrderDeepEqualsVisitor;
 import li.strolch.model.visitor.ResourceDeepEqualsVisitor;
+import li.strolch.model.xml.OrderFromDomVisitor;
 import li.strolch.model.xml.OrderToDomVisitor;
+import li.strolch.model.xml.ResourceFromDomVisitor;
 import li.strolch.model.xml.ResourceToDomVisitor;
 
 import org.junit.Test;
 import org.w3c.dom.Document;
-import org.w3c.dom.Element;
 
 /**
  * @author Robert von Burg <eitch@eitchnet.ch>
@@ -40,8 +41,7 @@ public class XmlToDomTest extends ModelTest {
 		domVisitor.visit(order);
 		Document document = domVisitor.getDocument();
 
-		Element rootElement = document.getDocumentElement();
-		Order parsedOrder = new Order(rootElement);
+		Order parsedOrder = new OrderFromDomVisitor().visit(document);
 
 		OrderDeepEqualsVisitor visitor = new OrderDeepEqualsVisitor(order);
 		visitor.visit(parsedOrder);
@@ -57,8 +57,7 @@ public class XmlToDomTest extends ModelTest {
 		domVisitor.visit(resource);
 		Document document = domVisitor.getDocument();
 
-		Element rootElement = document.getDocumentElement();
-		Resource parsedResource = new Resource(rootElement);
+		Resource parsedResource = new ResourceFromDomVisitor().visit(document);
 
 		ResourceDeepEqualsVisitor visitor = new ResourceDeepEqualsVisitor(resource);
 		visitor.visit(parsedResource);
diff --git a/li.strolch.model/src/test/java/li/strolch/model/activity/ActionTest.java b/li.strolch.model/src/test/java/li/strolch/model/activity/ActionTest.java
index 57633d2ce..a70751bf9 100644
--- a/li.strolch.model/src/test/java/li/strolch/model/activity/ActionTest.java
+++ b/li.strolch.model/src/test/java/li/strolch/model/activity/ActionTest.java
@@ -18,6 +18,7 @@ import javax.xml.transform.stream.StreamResult;
 import li.strolch.model.timevalue.IValueChange;
 import li.strolch.model.timevalue.impl.IntegerValue;
 import li.strolch.model.timevalue.impl.ValueChange;
+import li.strolch.model.xml.ActivityToDomVisitor;
 
 import org.junit.Assert;
 import org.junit.Before;
@@ -76,7 +77,7 @@ public class ActionTest {
 
 		DocumentBuilder db = DocumentBuilderFactory.newInstance().newDocumentBuilder();
 		Document document = db.newDocument();
-		Element dom = this.action.toDom(document);
+		Element dom = new ActivityToDomVisitor().toDom(this.action);
 		document.appendChild(dom);
 
 		Transformer transformer = TransformerFactory.newInstance().newTransformer();
diff --git a/li.strolch.model/src/test/java/li/strolch/model/activity/ActivityTest.java b/li.strolch.model/src/test/java/li/strolch/model/activity/ActivityTest.java
index 16047919b..95bf8847d 100644
--- a/li.strolch.model/src/test/java/li/strolch/model/activity/ActivityTest.java
+++ b/li.strolch.model/src/test/java/li/strolch/model/activity/ActivityTest.java
@@ -13,6 +13,7 @@ import javax.xml.transform.stream.StreamResult;
 
 import li.strolch.exception.StrolchException;
 import li.strolch.model.State;
+import li.strolch.model.xml.ActivityToDomVisitor;
 
 import org.junit.Assert;
 import org.junit.Before;
@@ -128,7 +129,7 @@ public class ActivityTest {
 		DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
 		DocumentBuilder db = dbf.newDocumentBuilder();
 		Document document = db.newDocument();
-		Element dom = this.activity.toDom(document);
+		Element dom = new ActivityToDomVisitor().toDom(this.activity);
 		document.appendChild(dom);
 
 		Transformer transformer = TransformerFactory.newInstance().newTransformer();
diff --git a/li.strolch.model/src/test/resources/data/activities/Activities.xml b/li.strolch.model/src/test/resources/data/activities/Activities.xml
index be58063a8..3efad9741 100644
--- a/li.strolch.model/src/test/resources/data/activities/Activities.xml
+++ b/li.strolch.model/src/test/resources/data/activities/Activities.xml
@@ -1,12 +1,108 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <StrolchModel>
 
-	<Activity Id="activity" Name="Activity" Type="parentType">
-		<Action Id="action_1" Name="Action 1" ResourceId="dummyId" ResourceType="dummyType" State="CREATED" Type="Use" />
+	<Activity Id="activity_1" Name="Activity" Type="parentType">
+		<Action Id="action_1" Name="Action 1" ResourceId="dummyId" ResourceType="dummyType" State="CREATED" Type="Use">
+			<ValueChange StateId="dummyId" Time="2012-11-30T18:12:05.628+01:00" Value="5" Type="Integer" />
+		</Action>
 		<Activity Id="child_activity" Name="Child Activity" Type="childType">
 			<Action Id="action_2" Name="Action 2" ResourceId="dummyId" ResourceType="dummyType" State="PLANNED" Type="Use" />
 			<Action Id="action_3" Name="Action 3" ResourceId="dummyId" ResourceType="dummyType" State="CREATED" Type="Use" />
 		</Activity>
 	</Activity>
 
+	<Activity Id="activity_2" Name="Activity" Type="parentType">
+		<ParameterBag Id="@bag01" Name="Test Bag" Type="TestBag">
+			<Parameter Id="@param8" Name="Duration Param" Type="Duration" Value="P1D" />
+			<Parameter Id="@param7" Name="StringList Param" Type="StringList" Value="Hello;World" />
+			<Parameter Id="@param6" Name="Date Param" Type="Date" Value="2012-11-30T18:12:05.628+01:00" />
+			<Parameter Id="@param5" Name="String Param" Type="String" Value="Strolch" />
+			<Parameter Id="@param4" Name="Long Param" Type="Long" Value="4453234566" />
+			<Parameter Id="@param3" Name="Integer Param" Type="Integer" Value="77" />
+			<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
+			<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
+		</ParameterBag>
+		<Action Id="action_1" Name="Action 1" ResourceId="dummyId" ResourceType="dummyType" State="CREATED" Type="Use">
+			<ParameterBag Id="@bag01" Name="Test Bag" Type="TestBag">
+				<Parameter Id="@param8" Name="Duration Param" Type="Duration" Value="P1D" />
+				<Parameter Id="@param7" Name="StringList Param" Type="StringList" Value="Hello;World" />
+				<Parameter Id="@param6" Name="Date Param" Type="Date" Value="2012-11-30T18:12:05.628+01:00" />
+				<Parameter Id="@param5" Name="String Param" Type="String" Value="Strolch" />
+				<Parameter Id="@param4" Name="Long Param" Type="Long" Value="4453234566" />
+				<Parameter Id="@param3" Name="Integer Param" Type="Integer" Value="77" />
+				<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
+				<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
+			</ParameterBag>
+		</Action>
+		<Activity Id="child_activity" Name="Child Activity" Type="childType">
+			<ParameterBag Id="@bag01" Name="Test Bag" Type="TestBag">
+				<Parameter Id="@param8" Name="Duration Param" Type="Duration" Value="P1D" />
+				<Parameter Id="@param7" Name="StringList Param" Type="StringList" Value="Hello;World" />
+				<Parameter Id="@param6" Name="Date Param" Type="Date" Value="2012-11-30T18:12:05.628+01:00" />
+				<Parameter Id="@param5" Name="String Param" Type="String" Value="Strolch" />
+				<Parameter Id="@param4" Name="Long Param" Type="Long" Value="4453234566" />
+				<Parameter Id="@param3" Name="Integer Param" Type="Integer" Value="77" />
+				<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
+				<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
+			</ParameterBag>
+			<Action Id="action_2" Name="Action 2" ResourceId="dummyId" ResourceType="dummyType" State="PLANNED" Type="Use">
+				<ParameterBag Id="@bag01" Name="Test Bag" Type="TestBag">
+					<Parameter Id="@param8" Name="Duration Param" Type="Duration" Value="P1D" />
+					<Parameter Id="@param7" Name="StringList Param" Type="StringList" Value="Hello;World" />
+					<Parameter Id="@param6" Name="Date Param" Type="Date" Value="2012-11-30T18:12:05.628+01:00" />
+					<Parameter Id="@param5" Name="String Param" Type="String" Value="Strolch" />
+					<Parameter Id="@param4" Name="Long Param" Type="Long" Value="4453234566" />
+					<Parameter Id="@param3" Name="Integer Param" Type="Integer" Value="77" />
+					<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
+					<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
+				</ParameterBag>
+			</Action>
+			<Action Id="action_3" Name="Action 3" ResourceId="dummyId" ResourceType="dummyType" State="CREATED" Type="Use">
+				<ParameterBag Id="@bag01" Name="Test Bag" Type="TestBag">
+					<Parameter Id="@param8" Name="Duration Param" Type="Duration" Value="P1D" />
+					<Parameter Id="@param7" Name="StringList Param" Type="StringList" Value="Hello;World" />
+					<Parameter Id="@param6" Name="Date Param" Type="Date" Value="2012-11-30T18:12:05.628+01:00" />
+					<Parameter Id="@param5" Name="String Param" Type="String" Value="Strolch" />
+					<Parameter Id="@param4" Name="Long Param" Type="Long" Value="4453234566" />
+					<Parameter Id="@param3" Name="Integer Param" Type="Integer" Value="77" />
+					<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
+					<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
+				</ParameterBag>
+			</Action>
+		</Activity>
+	</Activity>
+
+	<Activity Id="activity_3" Name="Activity" Type="parentType">
+		<ParameterBag Id="@bag01" Name="Test Bag" Type="TestBag">
+			<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
+			<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
+		</ParameterBag>
+		<Action Id="action_1" Name="Action 1" ResourceId="dummyId" ResourceType="dummyType" State="CREATED" Type="Use">
+			<ParameterBag Id="@bag01" Name="Test Bag" Type="TestBag">
+				<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
+				<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
+			</ParameterBag>
+		</Action>
+		<Activity Id="child_activity" Name="Child Activity" Type="childType">
+			<Action Id="action_2" Name="Action 2" ResourceId="dummyId" ResourceType="dummyType" State="PLANNED" Type="Use">
+				<ParameterBag Id="@bag01" Name="Test Bag" Type="TestBag">
+					<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
+					<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
+				</ParameterBag>
+			</Action>
+			<Activity Id="child_child_activity" Name="Child Activity" Type="childType">
+				<ParameterBag Id="@bag01" Name="Test Bag" Type="TestBag">
+					<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
+					<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
+				</ParameterBag>
+				<Action Id="action_3" Name="Action 3" ResourceId="dummyId" ResourceType="dummyType" State="CREATED" Type="Use">
+					<ParameterBag Id="@bag01" Name="Test Bag" Type="TestBag">
+						<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
+						<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
+					</ParameterBag>
+				</Action>
+			</Activity>
+		</Activity>
+	</Activity>
+
 </StrolchModel>
\ No newline at end of file
diff --git a/li.strolch.model/src/test/resources/data/resources/Resources.xml b/li.strolch.model/src/test/resources/data/resources/Resources.xml
index fcbb0f7d2..a9efa557b 100644
--- a/li.strolch.model/src/test/resources/data/resources/Resources.xml
+++ b/li.strolch.model/src/test/resources/data/resources/Resources.xml
@@ -14,12 +14,12 @@
 			<Parameter Id="@param2" Name="Float Param" Type="Float" Value="44.3" />
 			<Parameter Id="@param1" Name="Boolean Param" Type="Boolean" Value="true" />
 		</ParameterBag>
-		<TimedState Id="@booleanState" Name="Boolean State" Type="BooleanState">
+		<TimedState Id="@booleanState" Name="Boolean State" Type="Boolean">
 			<Value Time="1970-01-01T00:00:00.000+01:00" Value="false" />
 			<Value Time="1970-01-01T00:01:00.000+01:00" Value="true" />
 			<Value Time="1970-01-01T00:02:00.000+01:00" Value="false" />
 		</TimedState>
-		<TimedState Id="@integerState" Name="Integer State" Type="IntegerState">
+		<TimedState Id="@integerState" Name="Integer State" Type="Integer">
 			<Value Time="1970-01-01T00:00:00.000+01:00" Value="1" />
 			<Value Time="1970-01-01T00:01:00.000+01:00" Value="2" />
 			<Value Time="1970-01-01T00:02:00.000+01:00" Value="3" />
@@ -27,7 +27,7 @@
 			<Value Time="1970-01-01T00:04:00.000+01:00" Value="1" />
 			<Value Time="1970-01-01T00:05:00.000+01:00" Value="0" />
 		</TimedState>
-		<TimedState Id="@floatState" Name="Float State" Type="FloatState">
+		<TimedState Id="@floatState" Name="Float State" Type="Float">
 			<Value Time="1970-01-01T00:00:00.000+01:00" Value="1.1" />
 			<Value Time="1970-01-01T00:01:00.000+01:00" Value="2.2" />
 			<Value Time="1970-01-01T00:02:00.000+01:00" Value="3.3" />
@@ -35,7 +35,7 @@
 			<Value Time="1970-01-01T00:04:00.000+01:00" Value="1.1" />
 			<Value Time="1970-01-01T00:05:00.000+01:00" Value="0.0" />
 		</TimedState>
-		<TimedState Id="@stringSetState" Name="StringSet State" Type="StringSetState">
+		<TimedState Id="@stringSetState" Name="StringSet State" Type="StringSet">
 			<Value Time="1970-01-01T00:00:00.000+01:00" Value="foo" />
 			<Value Time="1970-01-01T00:01:00.000+01:00" Value="foo, bar" />
 			<Value Time="1970-01-01T00:02:00.000+01:00" Value="bar" />
diff --git a/li.strolch.service/src/main/java/li/strolch/command/ClearModelCommand.java b/li.strolch.service/src/main/java/li/strolch/command/ClearModelCommand.java
index f2d935c9b..1bbbfb2ea 100644
--- a/li.strolch.service/src/main/java/li/strolch/command/ClearModelCommand.java
+++ b/li.strolch.service/src/main/java/li/strolch/command/ClearModelCommand.java
@@ -15,6 +15,7 @@
  */
 package li.strolch.command;
 
+import li.strolch.agent.api.ActivityMap;
 import li.strolch.agent.api.ComponentContainer;
 import li.strolch.agent.api.OrderMap;
 import li.strolch.agent.api.ResourceMap;
@@ -30,6 +31,7 @@ public class ClearModelCommand extends Command {
 	// input
 	private boolean clearOrders;
 	private boolean clearResources;
+	private boolean clearActivities;
 
 	// output
 	private ModelStatistics statistics;
@@ -62,6 +64,11 @@ public class ClearModelCommand extends Command {
 			statistics.nrOfResources = resourceMap.removeAll(tx());
 		}
 
+		if (this.clearActivities) {
+			ActivityMap activitiesMap = tx().getActivityMap();
+			statistics.nrOfActivities = activitiesMap.removeAll(tx());
+		}
+
 		this.statistics = statistics;
 	}
 
@@ -86,6 +93,14 @@ public class ClearModelCommand extends Command {
 		this.clearResources = clearResources;
 	}
 
+	/**
+	 * @param clearActivities
+	 *            the clearActivities to set
+	 */
+	public void setClearActivities(boolean clearActivities) {
+		this.clearActivities = clearActivities;
+	}
+
 	/**
 	 * @return the statistics
 	 */
diff --git a/li.strolch.service/src/main/java/li/strolch/command/XmlExportModelCommand.java b/li.strolch.service/src/main/java/li/strolch/command/XmlExportModelCommand.java
index 7f2408b0c..ca67462ea 100644
--- a/li.strolch.service/src/main/java/li/strolch/command/XmlExportModelCommand.java
+++ b/li.strolch.service/src/main/java/li/strolch/command/XmlExportModelCommand.java
@@ -34,16 +34,19 @@ import javax.xml.stream.XMLOutputFactory;
 import javax.xml.stream.XMLStreamException;
 import javax.xml.stream.XMLStreamWriter;
 
+import li.strolch.agent.api.ActivityMap;
 import li.strolch.agent.api.ComponentContainer;
 import li.strolch.agent.api.OrderMap;
 import li.strolch.agent.api.ResourceMap;
 import li.strolch.exception.StrolchException;
+import li.strolch.model.ActivityVisitor;
 import li.strolch.model.ModelStatistics;
 import li.strolch.model.Order;
 import li.strolch.model.OrderVisitor;
 import li.strolch.model.Resource;
 import li.strolch.model.ResourceVisitor;
 import li.strolch.model.Tags;
+import li.strolch.model.activity.Activity;
 import li.strolch.model.xml.OrderToSaxWriterVisitor;
 import li.strolch.model.xml.ResourceToSaxWriterVisitor;
 import li.strolch.persistence.api.StrolchTransaction;
@@ -262,6 +265,17 @@ public class XmlExportModelCommand extends Command {
 		}
 	}
 
+	private void writeActivitiesByType(XMLStreamWriter writer, ActivityMap activityMap, String type) {
+		ActivityVisitor<?> visitor = new ActivityToSaxWriterVisitor(writer);
+		Set<String> keysByType = new TreeSet<>(activityMap.getKeysBy(tx(), type));
+		for (String id : keysByType) {
+			Activity activity = activityMap.getBy(tx(), type, id);
+			visitor.visit(activity);
+			this.statistics.nrOfActivities++;
+			logElementsWritten();
+		}
+	}
+
 	private XMLStreamWriter openXmlStreamWriter(FileOutputStream out) throws FactoryConfigurationError,
 			XMLStreamException {
 		XMLOutputFactory factory = XMLOutputFactory.newInstance();