Bug 512554 - [Architecture-General] No Disable Workspace Model Indexer facility

- Start indexing in the moment that a first demand for an index (instance of class CrossReferenceIndex) is done.

- The ControlledUnitLabelDecorator is already used earlier (if the project explorer is
  open). With the patch, it will only start decorating, once indexing has been started, i.e. a
  Papyrus model is opened. This means that decorations are available late, but avoids starting
  the indexer almost immediately (for sporadic Papyrus users)

- Increase wait timeout added in bug 512554: otherwise we might run regularly into a
  timeout due to class loading delays

Change-Id: I9084f3c4f3023c25d32fa35ade7ae67900439eca

1 files changed, 25 insertions, 10 deletions

diff --git a/plugins/infra/services/org.eclipse.papyrus.infra.services.controlmode/src/org/eclipse/papyrus/infra/services/controlmode/internal/ui/ControlledUnitLabelDecorator.java b/plugins/infra/services/org.eclipse.papyrus.infra.services.controlmode/src/org/eclipse/papyrus/infra/services/controlmode/internal/ui/ControlledUnitLabelDecorator.java
index e80bbe48a12..53e7e60bbe8 100644
--- a/plugins/infra/services/org.eclipse.papyrus.infra.services.controlmode/src/org/eclipse/papyrus/infra/services/controlmode/internal/ui/ControlledUnitLabelDecorator.java
+++ b/plugins/infra/services/org.eclipse.papyrus.infra.services.controlmode/src/org/eclipse/papyrus/infra/services/controlmode/internal/ui/ControlledUnitLabelDecorator.java
@@ -27,6 +27,7 @@ import org.eclipse.jface.viewers.IDecoration;
 import org.eclipse.jface.viewers.ILightweightLabelDecorator;
 import org.eclipse.jface.viewers.LabelProviderChangedEvent;
 import org.eclipse.papyrus.infra.emf.internal.resource.CrossReferenceIndex;
+import org.eclipse.papyrus.infra.emf.internal.resource.index.IndexManager;
 import org.eclipse.papyrus.infra.emf.resource.ICrossReferenceIndex;
 import org.eclipse.papyrus.infra.onefile.model.IPapyrusFile;
 import org.eclipse.papyrus.infra.services.controlmode.ControlModePlugin;
@@ -50,12 +51,7 @@ public class ControlledUnitLabelDecorator extends BaseLabelProvider implements I
 	 */
 	public ControlledUnitLabelDecorator() {
 		super();
-
-		// A very coarse-grained label change event
-		index = CrossReferenceIndex.getInstance();
-		unregisterHandler = CrossReferenceIndex.getInstance().onIndexChanged(
-				__ -> fireLabelProviderChanged(new LabelProviderChangedEvent(this)),
-				CoreExecutors.getUIExecutorService());
+		index = null;
 	}
 
 	@Override
@@ -72,13 +68,32 @@ public class ControlledUnitLabelDecorator extends BaseLabelProvider implements I
 
 	@Override
 	public void decorate(Object element, IDecoration decoration) {
-		if (element instanceof IFile) {
-			decorateFile((IFile) element, decoration);
-		} else if (element instanceof IPapyrusFile) {
-			decorateFile((IPapyrusFile) element, decoration);
+		if (IndexManager.getInstance().isStarted()) {
+			if (element instanceof IFile) {
+				checkIndex();
+				decorateFile((IFile) element, decoration);
+			} else if (element instanceof IPapyrusFile) {
+				checkIndex();
+				decorateFile((IPapyrusFile) element, decoration);
+			}
 		}
 	}
 
+	/**
+	 * check whether index reference is already initialized, register listener
+	 * and initialize index variable
+	 */
+	private void checkIndex() {
+		if (index == null) {
+			index = CrossReferenceIndex.getInstance();
+
+			// A very coarse-grained label change event
+			unregisterHandler = ((CrossReferenceIndex) index).onIndexChanged(
+					__ -> fireLabelProviderChanged(new LabelProviderChangedEvent(this)),
+				CoreExecutors.getUIExecutorService());
+		}
+	}
+	
 	private void decorateFile(IFile file, IDecoration decoration) {
 		ListenableFuture<SubunitKind> futureKind = getSubunitKind(file);
 		if (futureKind.isDone()) {