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 c24214cce..e633ae93f 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
@@ -71,6 +71,16 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 			this.changes = new ArrayList<>();
 	}
 
+	@Override
+	public boolean isAction() {
+		return true;
+	}
+
+	@Override
+	public boolean isActivity() {
+		return false;
+	}
+
 	/**
 	 * @return the id of the {@link Resource} the {@link Action} acts on
 	 */
@@ -88,7 +98,7 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 	}
 
 	/**
-	 * @return the current <code>State</code> of the a<code>Action</code>
+	 * @return the current {@code State} of the a {@code Action}
 	 */
 	@Override
 	public State getState() {
@@ -97,7 +107,7 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 
 	/**
 	 * @param state
-	 * 		the target <code>State</code> of the a<code>Action</code>
+	 * 		the target {@code State} of the a {@code Action}
 	 */
 	public void setState(State state) {
 		assertNotReadonly();
@@ -105,7 +115,7 @@ 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} this {@code Action} acts on
 	 */
 	public String getResourceType() {
 		return this.resourceType;
@@ -131,7 +141,7 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 
 	/**
 	 * @param change
-	 * 		<code>IValueChange</code> to be applied to the <code>Resource</code>
+	 * 		{@code IValueChange} to be applied to the {@code Resource}
 	 *
 	 * @return <tt>true</tt> (as specified by {@link Collection#add})
 	 */
@@ -142,7 +152,7 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 	}
 
 	/**
-	 * @return the list of <code>IValueChange</code> attached to the <code>Action</code> start
+	 * @return the list of {@code IValueChange} attached to the {@code Action} start
 	 */
 	public List<IValueChange<? extends IValue<?>>> getChanges() {
 		if (this.changes == null)
@@ -274,7 +284,7 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 
 	@Override
 	public Long getStart() {
-		Long start = Long.MAX_VALUE;
+		long start = Long.MAX_VALUE;
 		if (this.changes == null)
 			return start;
 		for (IValueChange<?> change : this.changes) {
@@ -285,7 +295,7 @@ public class Action extends GroupedParameterizedElement implements IActivityElem
 
 	@Override
 	public Long getEnd() {
-		Long end = 0L;
+		long end = 0L;
 		if (this.changes == null)
 			return end;
 		for (IValueChange<?> change : this.changes) {
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 185066a45..d191139c9 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
@@ -115,6 +115,16 @@ public class Activity extends AbstractStrolchRootElement
 		}
 	}
 
+	@Override
+	public boolean isAction() {
+		return false;
+	}
+
+	@Override
+	public boolean isActivity() {
+		return true;
+	}
+
 	/**
 	 * Returns true if this {@link Activity} contains any children i.e. any of {@link Action} or {@link Activity}
 	 *
@@ -139,7 +149,7 @@ public class Activity extends AbstractStrolchRootElement
 	}
 
 	/**
-	 * add an activity element to the <code>LinkedHashMap</code> of <code>IActivityElements</code>
+	 * add an activity element to the {@code LinkedHashMap} of {@code IActivityElements}
 	 *
 	 * @param activityElement
 	 * 		the element to add
@@ -185,10 +195,10 @@ public class Activity extends AbstractStrolchRootElement
 	}
 
 	/**
-	 * get <code>IActivityElement</code> by id
+	 * get {@code IActivityElement} by id
 	 *
 	 * @param id
-	 * 		the id of the <code>IActivityElement</code>
+	 * 		the id of the {@code IActivityElement}
 	 *
 	 * @return IActivityElement
 	 */
@@ -291,7 +301,7 @@ public class Activity extends AbstractStrolchRootElement
 	}
 
 	/**
-	 * @return get the <code>LinkedHashMap</code> of <code>IActivityElements</code>
+	 * @return get the {@code LinkedHashMap} of {@code IActivityElements}
 	 */
 	public Map<String, IActivityElement> getElements() {
 		if (this.elements == null)
@@ -385,7 +395,7 @@ public class Activity extends AbstractStrolchRootElement
 
 	@Override
 	public Long getStart() {
-		Long start = Long.MAX_VALUE;
+		long start = Long.MAX_VALUE;
 		if (this.elements == null)
 			return start;
 		Iterator<Entry<String, IActivityElement>> elementIterator = elementIterator();
@@ -398,7 +408,7 @@ public class Activity extends AbstractStrolchRootElement
 
 	@Override
 	public Long getEnd() {
-		Long end = 0L;
+		long end = 0L;
 		if (this.elements == null)
 			return end;
 		Iterator<Entry<String, IActivityElement>> elementIterator = elementIterator();
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 fd4fa00aa..f9f8b50aa 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
@@ -32,24 +32,35 @@ public interface IActivityElement extends StrolchElement {
 	/**
 	 * @return the start time of this element
 	 */
-	public Long getStart();
+	Long getStart();
 
 	/**
 	 * @return the end time of this element
 	 */
-	public Long getEnd();
+	Long getEnd();
 
 	/**
 	 * @return the {@link State} of this element
 	 */
-	public State getState();
+	State getState();
+
+	/**
+	 * @return true if this element is an {@link Action}
+	 */
+	boolean isAction();
+
+	/**
+	 * @return true if this element is an {@link Activity}
+	 */
+	boolean isActivity();
 
 	/**
 	 * Set the parent
 	 *
 	 * @param activity
+	 * 		the activity to set as parent
 	 */
-	public void setParent(Activity activity);
+	void setParent(Activity activity);
 
 	/**
 	 * <p>
@@ -63,7 +74,7 @@ public interface IActivityElement extends StrolchElement {
 	 *
 	 * @see GroupedParameterizedElement#getParameter(String, String)
 	 */
-	public <U, T extends Parameter<U>> T findParameter(String bagKey, String paramKey);
+	<U, T extends Parameter<U>> T findParameter(String bagKey, String paramKey);
 
 	/**
 	 * <p>
@@ -72,22 +83,22 @@ public interface IActivityElement extends StrolchElement {
 	 * </p>
 	 *
 	 * <p>
-	 * If the parameter does not exist and <code>assertExists</code> is true, then an
+	 * If the parameter does not exist and {@code assertExists} is true, then an
 	 * </p>
 	 *
 	 * @see GroupedParameterizedElement#getParameter(String, String, boolean)
 	 */
-	public <U, T extends Parameter<U>> T findParameter(String bagKey, String paramKey, boolean assertExists)
+	<U, T extends Parameter<U>> T findParameter(String bagKey, String paramKey, boolean assertExists)
 			throws StrolchModelException;
 
 	@Override
-	public Activity getParent();
+	Activity getParent();
 
 	@Override
-	public Activity getRootElement();
+	Activity getRootElement();
 
 	@Override
-	public IActivityElement getClone();
+	IActivityElement getClone();
 
 	/**
 	 * Implements the visitor pattern. Concrete implementation will call the proper method on the visitor
@@ -97,5 +108,5 @@ public interface IActivityElement extends StrolchElement {
 	 *
 	 * @return the result of the visitor being accepted
 	 */
-	public <T> T accept(StrolchElementVisitor<T> visitor);
+	<T> T accept(StrolchElementVisitor<T> visitor);
 }