Bug 15844 [Exception Handling] SelectionChange events and NPE
Build 20020508 Due to new global actions there are now more objects listening to selection changes send out by a JFace viewer. We now had the case that one of the listener generated a NPE. As a result all listeners registered after that one didn't receive the selection change event. StructuredViewers should be more fault tolorant to exceptions when informing listeners.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
protected abstract boolean getExpanded(Item item);
/**
 * Returns a list of elements corresponding to expanded nodes in this
 * viewer's tree, including currently hidden ones that are marked as
 * expanded but are under a collapsed ancestor.
 * <p>
 * This method is typically used when preserving the interesting
 * state of a viewer; <code>setExpandedElements</code> is used during the restore.
 * </p>
 *
 * @return the array of expanded elements
 *
 * @see #setExpandedElements
 */
public Object[] getExpandedElements() {
	ArrayList v= new ArrayList();
	internalCollectExpanded(v, getControl());
	return v.toArray();
}
/**
 * Returns whether the node corresponding to the given element is expanded or collapsed.
 *
 * @param element the element
 * @return <code>true</code> if the node is expanded, and <code>false</code> if collapsed
 */
public boolean getExpandedState(Object element) {
	Widget item = findItem(element);
	if (item instanceof Item)
		return getExpanded((Item) item);
	return false;