Fixed model split example

 - added creation of event model file
 - model files are only written if related submodel is available
diff --git a/examples/app4mc.example.tool.java/src/app4mc/example/tool/java/SplitModelExample.java b/examples/app4mc.example.tool.java/src/app4mc/example/tool/java/SplitModelExample.java
index 5444115..0c358db 100644
--- a/examples/app4mc.example.tool.java/src/app4mc/example/tool/java/SplitModelExample.java
+++ b/examples/app4mc.example.tool.java/src/app4mc/example/tool/java/SplitModelExample.java
@@ -1,6 +1,6 @@
 /**
  ********************************************************************************
- * Copyright (c) 2018-2020 Robert Bosch GmbH.
+ * Copyright (c) 2018-2022 Robert Bosch GmbH.
  *
  * This program and the accompanying materials are made
  * available under the terms of the Eclipse Public License 2.0
@@ -71,6 +71,7 @@
 		Amalthea mSoftware		= createNewModelWithResource(resourceSet, "model-output/SplitModel/democar-sw.amxmi");
 		Amalthea mOS			= createNewModelWithResource(resourceSet, "model-output/SplitModel/democar-os.amxmi");
 		Amalthea mStimuli		= createNewModelWithResource(resourceSet, "model-output/SplitModel/democar-stimuli.amxmi");
+		Amalthea mEvents		= createNewModelWithResource(resourceSet, "model-output/SplitModel/democar-events.amxmi");
 		Amalthea mConstraints	= createNewModelWithResource(resourceSet, "model-output/SplitModel/democar-constraints.amxmi");
 		Amalthea mMapping		= createNewModelWithResource(resourceSet, "model-output/SplitModel/democar-mapping.amxmi");
 		Amalthea mComponents	= createNewModelWithResource(resourceSet, "model-output/SplitModel/democar-components.amxmi");
@@ -78,49 +79,73 @@
 		if (mCommon != null) {
 			mCommon.setCommonElements(inputModel.getCommonElements());
 			inputModel.setCommonElements(null);
-			writeResource(mCommon.eResource());
+			if (mCommon.getCommonElements() != null) {
+				writeResource(mCommon.eResource());				
+			}
 		}
 
 		if (mHardware != null) {
 			mHardware.setHwModel(inputModel.getHwModel());
 			inputModel.setHwModel(null);
-			writeResource(mHardware.eResource());
+			if (mHardware.getHwModel() != null) {
+				writeResource(mHardware.eResource());				
+			}
 		}
 
 		if (mSoftware != null) {
 			mSoftware.setSwModel(inputModel.getSwModel());
 			inputModel.setSwModel(null);
-			writeResource(mSoftware.eResource());
+			if (mSoftware.getSwModel() != null) {
+				writeResource(mSoftware.eResource());				
+			}
 		}
 
 		if (mOS != null) {
 			mOS.setOsModel(inputModel.getOsModel());
 			inputModel.setOsModel(null);
-			writeResource(mOS.eResource());
+			if (mOS.getOsModel() != null) {
+				writeResource(mOS.eResource());				
+			}
 		}
 
 		if (mStimuli != null) {
 			mStimuli.setStimuliModel(inputModel.getStimuliModel());
 			inputModel.setStimuliModel(null);
-			writeResource(mStimuli.eResource());
+			if (mStimuli.getStimuliModel() != null) {
+				writeResource(mStimuli.eResource());				
+			}
+		}
+
+		if (mEvents != null) {
+			mEvents.setEventModel(inputModel.getEventModel());
+			inputModel.setEventModel(null);
+			if (mEvents.getEventModel() != null) {
+				writeResource(mEvents.eResource());				
+			}
 		}
 
 		if (mConstraints != null) {
 			mConstraints.setConstraintsModel(inputModel.getConstraintsModel());
 			inputModel.setConstraintsModel(null);
-			writeResource(mConstraints.eResource());
+			if (mConstraints.getConstraintsModel() != null) {
+				writeResource(mConstraints.eResource());				
+			}
 		}
 
 		if (mMapping != null) {
 			mMapping.setMappingModel(inputModel.getMappingModel());
 			inputModel.setMappingModel(null);
-			writeResource(mMapping.eResource());
+			if (mMapping.getMappingModel() != null) {
+				writeResource(mMapping.eResource());				
+			}
 		}
 
 		if (mComponents != null) {
 			mComponents.setComponentsModel(inputModel.getComponentsModel());
 			inputModel.setComponentsModel(null);
-			writeResource(mComponents.eResource());
+			if (mComponents.getComponentsModel() != null) {
+				writeResource(mComponents.eResource());				
+			}
 		}
 
 		System.out.println("\ndone.");