Bug 568500 - [Diagram] Correct NPE

- Undo/Redo on an usaved programmatically created diagram

Change-Id: I49b8f09570129e016ad73fdedfa6d155753fe279
Signed-off-by: Quentin Le Menez <quentin.lemenez@cea.fr>

2 files changed, 22 insertions, 20 deletions

diff --git a/plugins/infra/emf/org.eclipse.papyrus.infra.emf/src/org/eclipse/papyrus/infra/emf/resource/ShardResourceHelper.java b/plugins/infra/emf/org.eclipse.papyrus.infra.emf/src/org/eclipse/papyrus/infra/emf/resource/ShardResourceHelper.java
index daa73648fe2..c7603f55806 100644
--- a/plugins/infra/emf/org.eclipse.papyrus.infra.emf/src/org/eclipse/papyrus/infra/emf/resource/ShardResourceHelper.java
+++ b/plugins/infra/emf/org.eclipse.papyrus.infra.emf/src/org/eclipse/papyrus/infra/emf/resource/ShardResourceHelper.java
@@ -1,6 +1,6 @@
 /*****************************************************************************
- * Copyright (c) 2016 Christian W. Damus and others.
- * 
+ * Copyright (c) 2016, 2020 Christian W. Damus and others.
+ *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
@@ -9,8 +9,9 @@
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
- *   Christian W. Damus - Initial API and implementation
- *   
+ *  Christian W. Damus - Initial API and implementation
+ *  Quentin Le Menez (CEA LIST) quentin.lemenez@cea.fr - Bug 568500
+ *
  *****************************************************************************/
 
 package org.eclipse.papyrus.infra.emf.resource;
@@ -46,7 +47,7 @@ import org.eclipse.papyrus.infra.tools.util.TypeUtils;
  * are dependent "shard" units of a Papyrus model. A shard helper must
  * always be {@linkplain #close() closed} after it is no longer needed,
  * because it attaches adapters to the model.
- * 
+ *
  * @since 2.1
  */
 public class ShardResourceHelper implements AutoCloseable {
@@ -64,10 +65,10 @@ public class ShardResourceHelper implements AutoCloseable {
 	 * Initializes me on a shard {@code resource} that is expected to contain
 	 * only one root element (it doesn't store multiple distinct sub-trees
 	 * of the model).
-	 * 
+	 *
 	 * @param resource
 	 *            a "resource" resource
-	 * 
+	 *
 	 * @see #ShardResourceHelper(EObject)
 	 */
 	public ShardResourceHelper(Resource resource) {
@@ -79,7 +80,7 @@ public class ShardResourceHelper implements AutoCloseable {
 	 * identifies a sub-tree of potentially more than one stored in the resource.
 	 * If there is any possibility that a resource stores multiple sub-trees,
 	 * prefer this constructor over {@linkplain #ShardResourceHelper(Resource) the other}.
-	 * 
+	 *
 	 * @param element
 	 *            an element in a "resource" resource
 	 */
@@ -96,7 +97,7 @@ public class ShardResourceHelper implements AutoCloseable {
 
 	/**
 	 * Is my resource a shard?
-	 * 
+	 *
 	 * @return whether my resource is a shard of its parent
 	 */
 	public boolean isShard() {
@@ -107,11 +108,11 @@ public class ShardResourceHelper implements AutoCloseable {
 	 * Changes my resource from a shard to an independent controlled unit, or vice-versa.
 	 * In the context of an editor and/or editing-domain, it is usually more appropriate
 	 * to use the {@link #getSetShardCommand(boolean)} API for manipulation by command.
-	 * 
+	 *
 	 * @param isShard
 	 *            whether my resource should be a shard. If it already matches
 	 *            this state, then do nothing
-	 * 
+	 *
 	 * @see #getSetShardCommand(boolean)
 	 */
 	public void setShard(boolean isShard) {
@@ -157,7 +158,7 @@ public class ShardResourceHelper implements AutoCloseable {
 	/**
 	 * Finds the element that is the root of the particular sub-tree stored in
 	 * this resource, from the context provided by the client.
-	 * 
+	 *
 	 * @return the shard root element as best determined from the context, or
 	 *         {@code null} in the worst case that the resource is empty
 	 */
@@ -188,13 +189,13 @@ public class ShardResourceHelper implements AutoCloseable {
 	/**
 	 * Obtains a command to change my resource from a shard to an independent
 	 * controlled unit, or vice-versa.
-	 * 
+	 *
 	 * @param isShard
 	 *            whether my resource should be a shard. If it already matches
 	 *            this state, then the resulting command will have no effect
-	 * 
+	 *
 	 * @return the set-shard command
-	 * 
+	 *
 	 * @see #setShard(boolean)
 	 */
 	public Command getSetShardCommand(boolean isShard) {
@@ -298,7 +299,7 @@ public class ShardResourceHelper implements AutoCloseable {
 
 	/**
 	 * Queries whether I have been {@linkplain #close() closed}.
-	 * 
+	 *
 	 * @return whether I have been closed
 	 */
 	public final boolean isClosed() {
@@ -325,7 +326,7 @@ public class ShardResourceHelper implements AutoCloseable {
 	private EAnnotation findAnnotation() {
 		EAnnotation result = null;
 
-		if (!resource.getContents().isEmpty()) {
+		if (null != resource && !resource.getContents().isEmpty()) {
 			EObject shardElement = getShardElement();
 			Notifier annotationOwner;
 
diff --git a/plugins/uml/diagram/org.eclipse.papyrus.uml.diagram.common/src/org/eclipse/papyrus/uml/diagram/common/util/CrossReferencerUtil.java b/plugins/uml/diagram/org.eclipse.papyrus.uml.diagram.common/src/org/eclipse/papyrus/uml/diagram/common/util/CrossReferencerUtil.java
index b19ad74e923..7e38f9bd9d7 100644
--- a/plugins/uml/diagram/org.eclipse.papyrus.uml.diagram.common/src/org/eclipse/papyrus/uml/diagram/common/util/CrossReferencerUtil.java
+++ b/plugins/uml/diagram/org.eclipse.papyrus.uml.diagram.common/src/org/eclipse/papyrus/uml/diagram/common/util/CrossReferencerUtil.java
@@ -10,6 +10,7 @@
  *
  * Contributors:
  *  Vincent Lorenzo (CEA LIST) vincent.lorenzo@cea.fr - Initial API and implementation
+ *  Quentin Le Menez (CEA LIST) quentin.lemenez@cea.fr - Bug 568500
  *
  *****************************************************************************/
 package org.eclipse.papyrus.uml.diagram.common.util;
@@ -62,7 +63,7 @@ public class CrossReferencerUtil {
 	 */
 	public static Set<View> getCrossReferencingViews(EObject referencedObject, String diagramType) {
 
-		Set<View> referencingObjects = new HashSet<View>();
+		Set<View> referencingObjects = new HashSet<>();
 
 		CrossReferenceAdapter crossReferenceAdapter = CrossReferencerUtil.getCrossReferenceAdapter(referencedObject);
 		if (crossReferenceAdapter != null) {
@@ -77,7 +78,7 @@ public class CrossReferencerUtil {
 
 					// Check if current view is owned by a diagram which type
 					// conforms to diagramType
-					if (diagramType.equals(view.getDiagram().getType())) {
+					if (null != view.getDiagram() && diagramType.equals(view.getDiagram().getType())) {
 						referencingObjects.add(view);
 					}
 
@@ -103,7 +104,7 @@ public class CrossReferencerUtil {
 	 */
 	public static Set<View> getCrossReferencingViewsInDiagram(final EObject referencedObject, final Diagram diagram) {
 
-		Set<View> referencingObjects = new HashSet<View>();
+		Set<View> referencingObjects = new HashSet<>();
 
 		CrossReferenceAdapter crossReferenceAdapter = CrossReferencerUtil.getCrossReferenceAdapter(referencedObject);
 		if (crossReferenceAdapter != null) {