diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/SimpleStrolchElementListener.java b/li.strolch.model/src/main/java/li/strolch/model/xml/SimpleStrolchElementListener.java
index b676756af..b460bcd1d 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/xml/SimpleStrolchElementListener.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/SimpleStrolchElementListener.java
@@ -15,7 +15,11 @@
  */
 package li.strolch.model.xml;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Stream;
 
 import li.strolch.model.Order;
 import li.strolch.model.Resource;
@@ -30,31 +34,22 @@ import li.strolch.model.activity.Activity;
  */
 public class SimpleStrolchElementListener implements StrolchElementListener {
 
-	private Map<String, Resource> resources;
-	private Map<String, Order> orders;
-	private Map<String, Activity> activities;
+	private final Map<String, Resource> resources = new HashMap<>();
+	private final Map<String, Order> orders = new HashMap<>();
+	private final Map<String, Activity> activities = new HashMap<>();
 
 	@Override
 	public void notifyResource(Resource resource) {
-		if (this.resources == null) {
-			this.resources = new HashMap<>();
-		}
 		this.resources.put(resource.getId(), resource);
 	}
 
 	@Override
 	public void notifyOrder(Order order) {
-		if (this.orders == null) {
-			this.orders = new HashMap<>();
-		}
 		this.orders.put(order.getId(), order);
 	}
 
 	@Override
 	public void notifyActivity(Activity activity) {
-		if (this.activities == null) {
-			this.activities = new HashMap<>();
-		}
 		this.activities.put(activity.getId(), activity);
 	}
 
@@ -71,20 +66,14 @@ public class SimpleStrolchElementListener implements StrolchElementListener {
 	}
 
 	public List<Resource> getResources() {
-		if (this.resources == null)
-			return Collections.emptyList();
 		return new ArrayList<>(this.resources.values());
 	}
 
 	public List<Order> getOrders() {
-		if (this.orders == null)
-			return Collections.emptyList();
 		return new ArrayList<>(this.orders.values());
 	}
 
 	public List<Activity> getActivities() {
-		if (this.activities == null)
-			return Collections.emptyList();
 		return new ArrayList<>(this.activities.values());
 	}
 
@@ -95,4 +84,9 @@ public class SimpleStrolchElementListener implements StrolchElementListener {
 		elements.addAll(getActivities());
 		return elements;
 	}
+
+	public Stream<StrolchRootElement> streamElements() {
+		return Stream.concat(this.resources.values().stream(),
+				Stream.concat(this.orders.values().stream(), this.activities.values().stream()));
+	}
 }
diff --git a/li.strolch.model/src/main/java/li/strolch/model/xml/StrolchXmlHelper.java b/li.strolch.model/src/main/java/li/strolch/model/xml/StrolchXmlHelper.java
index ae148cf81..3d0665e3a 100644
--- a/li.strolch.model/src/main/java/li/strolch/model/xml/StrolchXmlHelper.java
+++ b/li.strolch.model/src/main/java/li/strolch/model/xml/StrolchXmlHelper.java
@@ -15,7 +15,9 @@ import java.nio.file.Files;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 import javanet.staxutils.IndentingXMLStreamWriter;
 import li.strolch.model.Order;
@@ -62,6 +64,12 @@ public class StrolchXmlHelper {
 		return elementListener.getElements();
 	}
 
+	public static Stream<StrolchRootElement> parseFileAsStream(File file) {
+		SimpleStrolchElementListener elementListener = new SimpleStrolchElementListener();
+		new XmlModelSaxFileReader(elementListener, file, false).parseFile();
+		return elementListener.streamElements();
+	}
+
 	public static List<StrolchRootElement> parseStream(InputStream stream, String encoding) {
 		SimpleStrolchElementListener elementListener = new SimpleStrolchElementListener();
 		new XmlModelSaxStreamReader(elementListener, stream, encoding).parseStream();
@@ -78,6 +86,17 @@ public class StrolchXmlHelper {
 		logger.info("Wrote " + elements.size() + " elements to file " + file);
 	}
 
+	public static void writeToFile(File file, Stream<? extends StrolchRootElement> elements) {
+		int size;
+		try (OutputStream out = Files.newOutputStream(file.toPath())) {
+			size = writeToStream(out, elements);
+		} catch (Exception e) {
+			throw new RuntimeException("Failed to write elements to " + file, e);
+		}
+
+		logger.info("Wrote " + size + " elements to file " + file);
+	}
+
 	public static void writeToWriter(Writer writer, Collection<? extends StrolchRootElement> elements) {
 		try {
 			XMLStreamWriter xmlStreamWriter = prepareXmlStreamWriter(writer);
@@ -95,16 +114,19 @@ public class StrolchXmlHelper {
 
 	public static void writeToStream(OutputStream out, Collection<? extends StrolchRootElement> elements)
 			throws Exception {
-
 		XMLStreamWriter writer = prepareXmlStreamWriter(out);
-
-		for (StrolchRootElement element : elements) {
-			element.accept(new StrolchElementToSaxWriterVisitor(writer));
-		}
-
+		elements.forEach(element -> element.accept(new StrolchElementToSaxWriterVisitor(writer)));
 		writer.writeEndDocument();
 	}
 
+	public static int writeToStream(OutputStream out, Stream<? extends StrolchRootElement> elements) throws Exception {
+		XMLStreamWriter writer = prepareXmlStreamWriter(out);
+		AtomicInteger size = new AtomicInteger();
+		elements.peek(e -> size.incrementAndGet()).forEach(e -> e.accept(new StrolchElementToSaxWriterVisitor(writer)));
+		writer.writeEndDocument();
+		return size.get();
+	}
+
 	public static XMLStreamWriter prepareXmlStreamWriter(Writer writer)
 			throws FactoryConfigurationError, XMLStreamException {