1 files changed, 122 insertions, 0 deletions
diff --git a/dsf/org.eclipse.cdt.dsf.ui/src/org/eclipse/cdt/dsf/ui/viewmodel/VMChildrenUpdate.java b/dsf/org.eclipse.cdt.dsf.ui/src/org/eclipse/cdt/dsf/ui/viewmodel/VMChildrenUpdate.java
new file mode 100644
index 00000000000..73bcc1f9ea4
--- /dev/null
+++ b/dsf/org.eclipse.cdt.dsf.ui/src/org/eclipse/cdt/dsf/ui/viewmodel/VMChildrenUpdate.java
@@ -0,0 +1,122 @@
+/*******************************************************************************
+ * Copyright (c) 2007, 2008 Wind River Systems and others.
+ * 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:
+ *     Wind River Systems - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.dsf.ui.viewmodel;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.eclipse.cdt.dsf.concurrent.DataRequestMonitor;
+import org.eclipse.debug.internal.ui.viewers.model.provisional.IChildrenUpdate;
+import org.eclipse.debug.internal.ui.viewers.model.provisional.IModelDelta;
+import org.eclipse.debug.internal.ui.viewers.model.provisional.IPresentationContext;
+import org.eclipse.debug.internal.ui.viewers.model.provisional.IViewerUpdate;
+import org.eclipse.jface.viewers.TreePath;
+
+/** 
+ * Helper class implementation of the {@link IChildrenUpdate} update object.
+ * 
+ * @see VMViewerUpdate
+ */
+@SuppressWarnings("restriction")
+public class VMChildrenUpdate extends VMViewerUpdate implements IChildrenUpdate {
+    private final int fOffset;
+    private final int fLength;
+    protected final List<Object> fElements;
+    
+    public VMChildrenUpdate(IViewerUpdate clientUpdate, int offset, int length, 
+        DataRequestMonitor<List<Object>> requestMonitor) 
+    {
+        super(clientUpdate, requestMonitor);
+        fOffset = offset;
+        fLength = length;
+        fElements = length > 0 ? new ArrayList<Object>(length) : new ArrayList<Object>();
+    }
+
+    public VMChildrenUpdate(IModelDelta delta, IPresentationContext presentationContext, int offset, int length, 
+        DataRequestMonitor<List<Object>> rm) 
+    {
+        super(delta, presentationContext, rm);
+        fOffset = offset;
+        fLength = length;
+        fElements = length > 0 ? new ArrayList<Object>(length) : new ArrayList<Object>();
+    }
+
+    public VMChildrenUpdate(TreePath elementPath, Object viewerInput, IPresentationContext presentationContext, 
+        int offset, int length, DataRequestMonitor<List<Object>> rm) 
+    {
+        super(elementPath, viewerInput, presentationContext, rm);
+        fOffset = offset;
+        fLength = length;
+        fElements = length > 0 ? new ArrayList<Object>(length) : new ArrayList<Object>();
+    }
+
+    public int getOffset() {
+        return fOffset;
+    }
+
+    public int getLength() {
+        return fLength;
+    }
+
+    public void setChild(Object element, int offset) {
+        // Calculate the index in array based on configured offset.
+        int idx = offset - (fOffset > 0 ? fOffset : 0);
+        
+        // To make sure that index is in valid range.
+        if (idx < 0 || (fLength > 0 && idx >= fLength)) return;
+        
+        // Increase the list size if needed.
+        ensureElementsSize(idx + 1);
+        
+        // Finally set the element in elements list.
+        fElements.set(idx, element);
+    }
+
+    private void ensureElementsSize(int size) {
+        while (fElements.size() < size) {
+            fElements.add(null);
+        }
+    }
+        
+    @Override
+    public String toString() {
+        return "VMChildrenUpdate:" + getElement() + " {"+ getOffset() + "->" + (getOffset() + getLength()) + "}";  //$NON-NLS-1$ //$NON-NLS-2$//$NON-NLS-3$ //$NON-NLS-4$
+    }
+
+    @Override
+    public void done() {
+        @SuppressWarnings("unchecked")
+        DataRequestMonitor<List<Object>> rm = (DataRequestMonitor<List<Object>>)getRequestMonitor();
+        
+        /* See https://bugs.eclipse.org/bugs/show_bug.cgi?id=202109
+         * 
+         * A flexible hierarchy bug/optimization causes query with incorrect
+         * IChildrenUpdate[] array length.
+         *
+         * The problem manifests itself while deleting a register node. 
+         * For example, if the register view displays:
+         *     PC
+         *     EAX
+         *     EBX
+         *     ECX
+         *     EDX
+         *  And EBX is deleted, forcing a refresh, the viewer will query 
+         *  for IChildrenUpdate[5] and IChildrenCountUpdate at the same time.
+         *  
+         *  To avoid this problem do not generate an error if the list of 
+         *  children is smaller than the list of requested indexes.  Also,
+         *  do not check if any of the elements are null.
+         */        
+        rm.setData(fElements);
+        super.done();
+    }
+    
+}