Cleanup of some item providers
diff --git a/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/comp/extended/ExtendedCompositeIP.java b/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/comp/extended/ExtendedCompositeIP.java
index 43e7c21..b6361fe 100644
--- a/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/comp/extended/ExtendedCompositeIP.java
+++ b/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/comp/extended/ExtendedCompositeIP.java
@@ -40,8 +40,8 @@
 	protected CompConnectorContainerIP compConnectorCIP;
 	protected CompInstanceContainerIP compInstanceCIP;
 
-	private final EStructuralFeature feature_CONNECTORS = AmaltheaPackage.eINSTANCE.getISystem_Connectors();
-	private final EStructuralFeature feature_INSTANCES = AmaltheaPackage.eINSTANCE.getISystem_ComponentInstances();
+	private final EStructuralFeature featureCONNECTORS = AmaltheaPackage.eINSTANCE.getISystem_Connectors();
+	private final EStructuralFeature featureINSTANCES = AmaltheaPackage.eINSTANCE.getISystem_ComponentInstances();
 
 	public ExtendedCompositeIP(final AdapterFactory adapterFactory) {
 		super(adapterFactory);
@@ -64,8 +64,8 @@
 	@Override
 	public Collection<? extends EStructuralFeature> getChildrenFeatures(final Object object) {
 		super.getChildrenFeatures(object);
-		this.childrenFeatures.remove(this.feature_CONNECTORS);
-		this.childrenFeatures.remove(this.feature_INSTANCES);
+		this.childrenFeatures.remove(this.featureCONNECTORS);
+		this.childrenFeatures.remove(this.featureINSTANCES);
 		return this.childrenFeatures;
 	}
 
@@ -75,9 +75,9 @@
 		Composite composite = (Composite) object;
 		
 		// only display virtual folders if not empty (on top of the list)
-		if (composite.getComponentInstances().size() > 0)
+		if (!composite.getComponentInstances().isEmpty())
 			children.add(0, getCompInstanceContainerIP(composite));
-		if (composite.getConnectors().size() > 0)
+		if (!composite.getConnectors().isEmpty())
 			children.add(0, getCompConnectorContainerIP(composite));
 
 		// move ports to top of the list
@@ -101,15 +101,15 @@
 
 	protected Command createWrappedCommand(final Command command, final EObject owner,
 			final EStructuralFeature feature) {
-		if (feature == feature_CONNECTORS || feature == feature_INSTANCES) {
+		if (feature == featureCONNECTORS || feature == featureINSTANCES) {
 			return new CommandWrapper(command) {
 				@Override
 				public Collection<?> getAffectedObjects() {
 					Collection<?> affected = super.getAffectedObjects();
 					if (affected.contains(owner)) {
-						if (feature == feature_CONNECTORS) {
+						if (feature == featureCONNECTORS) {
 							affected = Collections.singleton(getCompConnectorContainerIP(((ISystem) owner)));
-						} else if (feature == feature_INSTANCES) {
+						} else if (feature == featureINSTANCES) {
 							affected = Collections.singleton(getCompInstanceContainerIP(((ISystem) owner)));
 						}
 					}
diff --git a/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/comp/extended/ExtendedSystemIP.java b/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/comp/extended/ExtendedSystemIP.java
index 10356e5..7ae0416 100644
--- a/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/comp/extended/ExtendedSystemIP.java
+++ b/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/comp/extended/ExtendedSystemIP.java
@@ -36,8 +36,8 @@
 	protected CompConnectorContainerIP compConnectorCIP;
 	protected CompInstanceContainerIP compInstanceCIP;
 
-	private final EStructuralFeature feature_CONNECTORS = AmaltheaPackage.eINSTANCE.getISystem_Connectors();
-	private final EStructuralFeature feature_INSTANCES = AmaltheaPackage.eINSTANCE.getISystem_ComponentInstances();
+	private final EStructuralFeature featureCONNECTORS = AmaltheaPackage.eINSTANCE.getISystem_Connectors();
+	private final EStructuralFeature featureINSTANCES = AmaltheaPackage.eINSTANCE.getISystem_ComponentInstances();
 
 	public ExtendedSystemIP(final AdapterFactory adapterFactory) {
 		super(adapterFactory);
@@ -60,8 +60,8 @@
 	@Override
 	public Collection<? extends EStructuralFeature> getChildrenFeatures(final Object object) {
 		super.getChildrenFeatures(object);
-		this.childrenFeatures.remove(this.feature_CONNECTORS);
-		this.childrenFeatures.remove(this.feature_INSTANCES);
+		this.childrenFeatures.remove(this.featureCONNECTORS);
+		this.childrenFeatures.remove(this.featureINSTANCES);
 		return this.childrenFeatures;
 	}
 
@@ -71,9 +71,9 @@
 		ISystem composite = (ISystem) object;
 		
 		// only display virtual folders if not empty (on top of the list)
-		if (composite.getComponentInstances().size() > 0)
+		if (!composite.getComponentInstances().isEmpty())
 			children.add(0, getCompInstanceContainerIP(composite));
-		if (composite.getConnectors().size() > 0)
+		if (!composite.getConnectors().isEmpty())
 			children.add(0, getCompConnectorContainerIP(composite));
 
 		return children;
@@ -93,15 +93,15 @@
 
 	protected Command createWrappedCommand(final Command command, final EObject owner,
 			final EStructuralFeature feature) {
-		if (feature == feature_CONNECTORS || feature == feature_INSTANCES) {
+		if (feature == featureCONNECTORS || feature == featureINSTANCES) {
 			return new CommandWrapper(command) {
 				@Override
 				public Collection<?> getAffectedObjects() {
 					Collection<?> affected = super.getAffectedObjects();
 					if (affected.contains(owner)) {
-						if (feature == feature_CONNECTORS) {
+						if (feature == featureCONNECTORS) {
 							affected = Collections.singleton(getCompConnectorContainerIP(((ISystem) owner)));
-						} else if (feature == feature_INSTANCES) {
+						} else if (feature == featureINSTANCES) {
 							affected = Collections.singleton(getCompInstanceContainerIP(((ISystem) owner)));
 						}
 					}
diff --git a/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/hw/extended/ExtendedHwStructureIP.java b/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/hw/extended/ExtendedHwStructureIP.java
index fdbf01e..070cb2e 100644
--- a/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/hw/extended/ExtendedHwStructureIP.java
+++ b/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/hw/extended/ExtendedHwStructureIP.java
@@ -36,8 +36,8 @@
 	protected HwConnectionContainerIP hwConnectionCIP;
 	protected HwModuleContainerIP hwModuleCIP;
 
-	private final EStructuralFeature feature_CONNECTIONS = AmaltheaPackage.eINSTANCE.getHwStructure_Connections();
-	private final EStructuralFeature feature_MODULES = AmaltheaPackage.eINSTANCE.getHwStructure_Modules();
+	private final EStructuralFeature featureCONNECTIONS = AmaltheaPackage.eINSTANCE.getHwStructure_Connections();
+	private final EStructuralFeature featureMODULES = AmaltheaPackage.eINSTANCE.getHwStructure_Modules();
 
 	public ExtendedHwStructureIP(final AdapterFactory adapterFactory) {
 		super(adapterFactory);
@@ -60,8 +60,8 @@
 	@Override
 	public Collection<? extends EStructuralFeature> getChildrenFeatures(final Object object) {
 		super.getChildrenFeatures(object);
-		this.childrenFeatures.remove(this.feature_CONNECTIONS);
-		this.childrenFeatures.remove(this.feature_MODULES);
+		this.childrenFeatures.remove(this.featureCONNECTIONS);
+		this.childrenFeatures.remove(this.featureMODULES);
 		return this.childrenFeatures;
 	}
 
@@ -71,9 +71,9 @@
 		HwStructure hwStruct = (HwStructure) object;
 		
 		// only display virtual folders if not empty (on top of the list)
-		if (hwStruct.getModules().size() > 0)
+		if (!hwStruct.getModules().isEmpty())
 			children.add(0, getModulesContainerIP(hwStruct));
-		if (hwStruct.getConnections().size() > 0)
+		if (!hwStruct.getConnections().isEmpty())
 			children.add(0, getConnectionsContainerIP(hwStruct));
 
 		// move ports to top of the list
@@ -97,15 +97,15 @@
 
 	protected Command createWrappedCommand(final Command command, final EObject owner,
 			final EStructuralFeature feature) {
-		if (feature == feature_CONNECTIONS || feature == feature_MODULES) {
+		if (feature == featureCONNECTIONS || feature == featureMODULES) {
 			return new CommandWrapper(command) {
 				@Override
 				public Collection<?> getAffectedObjects() {
 					Collection<?> affected = super.getAffectedObjects();
 					if (affected.contains(owner)) {
-						if (feature == feature_CONNECTIONS) {
+						if (feature == featureCONNECTIONS) {
 							affected = Collections.singleton(getConnectionsContainerIP(((HwStructure) owner)));
-						} else if (feature == feature_MODULES) {
+						} else if (feature == featureMODULES) {
 							affected = Collections.singleton(getModulesContainerIP(((HwStructure) owner)));
 						}
 					}
diff --git a/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/sw/extended/ExtendedRunnableIP.java b/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/sw/extended/ExtendedRunnableIP.java
index 341d908..f527cfc 100644
--- a/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/sw/extended/ExtendedRunnableIP.java
+++ b/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/edit/sw/extended/ExtendedRunnableIP.java
@@ -35,7 +35,7 @@
 
 	protected RunnableParametersContainerIP runnableParamsCIP;
 
-	private final EStructuralFeature feature_RUNNABLE_PARAMS = AmaltheaPackage.eINSTANCE.getRunnable_Parameters();
+	private final EStructuralFeature featurePARAMETERS = AmaltheaPackage.eINSTANCE.getRunnable_Parameters();
 
 	public ExtendedRunnableIP(final AdapterFactory adapterFactory) {
 		super(adapterFactory);
@@ -59,7 +59,7 @@
 	@Override
 	public Collection<? extends EStructuralFeature> getChildrenFeatures(final Object object) {
 		super.getChildrenFeatures(object);
-		this.childrenFeatures.remove(this.feature_RUNNABLE_PARAMS);
+		this.childrenFeatures.remove(this.featurePARAMETERS);
 		return this.childrenFeatures;
 	}
 
@@ -88,13 +88,13 @@
 
 	protected Command createWrappedCommand(final Command command, final EObject owner,
 			final EStructuralFeature feature) {
-		if (feature == feature_RUNNABLE_PARAMS) {
+		if (feature == featurePARAMETERS) {
 			return new CommandWrapper(command) {
 				@Override
 				public Collection<?> getAffectedObjects() {
 					Collection<?> affected = super.getAffectedObjects();
 					if (affected.contains(owner)) {
-						if (feature == feature_RUNNABLE_PARAMS) {
+						if (feature == featurePARAMETERS) {
 							affected = Collections.singleton(getRunnableParametersContainerIP(((Runnable) owner)));
 						}
 					}
diff --git a/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/provider/TransientItemProvider.java b/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/provider/TransientItemProvider.java
index cc6095e..9703d54 100644
--- a/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/provider/TransientItemProvider.java
+++ b/plugins/org.eclipse.app4mc.amalthea.model.edit.extended/src/org/eclipse/app4mc/amalthea/model/provider/TransientItemProvider.java
@@ -355,12 +355,7 @@
 	 */
 	protected Object wrap(Object object, EStructuralFeature feature, Object value, int index) {
 		if (!feature.isMany() && index != CommandParameter.NO_INDEX) {
-			System.out.println("Bad wrap index."); //$NON-NLS-1$
-			System.out.println("  object: " + object); //$NON-NLS-1$
-			System.out.println("  feature: " + feature); //$NON-NLS-1$
-			System.out.println("  value: " + value); //$NON-NLS-1$
-			System.out.println("  index: " + index); //$NON-NLS-1$
-			new IllegalArgumentException("Bad wrap index.").printStackTrace(); //$NON-NLS-1$
+			throw new IllegalArgumentException("Bad wrap index.");
 		}
 
 		Object wrapper = createWrapper(object, feature, value, index);
@@ -480,7 +475,7 @@
 
 				// These will be the children belonging to this feature.
 				//
-				Collection<Object> childrenOfThisFeature = new ArrayList<Object>();
+				Collection<Object> childrenOfThisFeature = new ArrayList<>();
 				childrenOfThisFeature.add(firstChild);
 				children.remove();