1 files changed, 76 insertions, 0 deletions
diff --git a/plugins/org.eclipse.etrice.ui.common/src/org/eclipse/etrice/ui/common/support/ChangeAwareCreateConnectionFeature.java b/plugins/org.eclipse.etrice.ui.common/src/org/eclipse/etrice/ui/common/support/ChangeAwareCreateConnectionFeature.java
new file mode 100644
index 000000000..90b222082
--- /dev/null
+++ b/plugins/org.eclipse.etrice.ui.common/src/org/eclipse/etrice/ui/common/support/ChangeAwareCreateConnectionFeature.java
@@ -0,0 +1,76 @@
+/*******************************************************************************
+ * Copyright (c) 2013 protos software gmbh (http://www.protos.de).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * 
+ * CONTRIBUTORS:
+ * 		Juergen Haug (initial contribution)
+ * 
+ *******************************************************************************/
+
+package org.eclipse.etrice.ui.common.support;
+
+import org.eclipse.emf.ecore.EObject;
+import org.eclipse.emf.ecore.change.ChangeDescription;
+import org.eclipse.emf.ecore.change.util.BasicChangeRecorder;
+import org.eclipse.emf.ecore.change.util.ChangeRecorder;
+import org.eclipse.graphiti.features.IFeatureProvider;
+import org.eclipse.graphiti.features.context.ICreateConnectionContext;
+import org.eclipse.graphiti.features.context.ICreateContext;
+import org.eclipse.graphiti.features.impl.AbstractCreateConnectionFeature;
+import org.eclipse.graphiti.features.impl.AbstractCreateFeature;
+import org.eclipse.graphiti.mm.pictograms.Connection;
+
+public abstract class ChangeAwareCreateConnectionFeature extends
+		AbstractCreateConnectionFeature {
+
+	boolean hasDoneChanges;
+	
+	public ChangeAwareCreateConnectionFeature(IFeatureProvider fp, String name,
+			String description) {
+		super(fp, name, description);
+		this.hasDoneChanges = false;
+	}
+
+	
+	@Override
+	public Connection create(ICreateConnectionContext context) {
+		EObject rootObject = getContainerModelObject(context);
+		BasicChangeRecorder changeRecorder = new ChangeRecorder(rootObject);
+
+		Connection result = doCreate(context);
+		boolean newObjects = result != null;
+
+		ChangeDescription cd = changeRecorder.endRecording();
+		hasDoneChanges = !(cd.getObjectChanges().isEmpty()
+				&& cd.getObjectsToAttach().isEmpty()
+				&& cd.getObjectsToDetach().isEmpty() && cd.getResourceChanges()
+				.isEmpty());
+
+		if (!newObjects && hasDoneChanges){
+			cd.apply();
+			hasDoneChanges = false;
+		}
+
+		return result;
+	}
+
+	@Override
+	public final boolean hasDoneChanges() {
+		return hasDoneChanges;
+	}
+	
+	/**
+	 * {@link AbstractCreateFeature#create(ICreateContext)}
+	 */
+	protected abstract Connection doCreate(ICreateConnectionContext context);
+
+	/**
+	 *  Return the model object, that holds all changed objects for the given context
+	 */
+	protected EObject getContainerModelObject(ICreateConnectionContext context){
+		return (EObject) getBusinessObjectForPictogramElement(getDiagram());
+	}
+}