Bug 32254 [Viewers] AbstractTreeViewer uses HashSet to remember expansion state
I20030216 The custom hash table should be used instead. Otherwise expansion state may be lost due to a different equals implementation of the element and the IElementComparer.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
}
/* (non-Javadoc)
 * Method declared in AbstractTreeViewer.
 */
protected Item[] getItems(Item item) {
	return ((TreeItem) item).getItems();
}
/**
 * The tree viewer implementation of this <code>Viewer</code> framework
 * method returns the label provider, which in the case of tree
 * viewers will be an instance of <code>ILabelProvider</code>.
 */
public IBaseLabelProvider getLabelProvider() {
	return super.getLabelProvider();
}
/* (non-Javadoc)
 * Method declared in AbstractTreeViewer.
 */
protected Item getParentItem(Item item) {
	return ((TreeItem)item).getParentItem();
}
/* (non-Javadoc)
 * Method declared in AbstractTreeViewer.
 */
protected Item[] getSelection(Control widget) {
	return ((Tree) widget).getSelection();
}
/**
 * Returns this tree viewer's tree control.
 *