Bug 306231 The Regular Expression Resource Filter must gracefully handle invalid patterns
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/dialogs/ResourceFilterGroup.java
public Object[] getChildren(Object parentElement) {
			if (parentElement instanceof FilterCopy)
				return ((FilterCopy) parentElement).getChildren();
			return null;
		}
		public Object getParent(Object element) {
			if (element instanceof FilterCopy) {
				if (((FilterCopy) element).getParent() != null)
					return ((FilterCopy) element).getParent();
				return filters;
			}
			return null;
		}
		public boolean hasChildren(Object element) {
			if (element instanceof FilterCopy) {
				FilterCopy[] children = ((FilterCopy) element).getChildren();
				return children != null && children.length > 0;
			}
			return false;
		}
		public Object[] getElements(Object inputElement) {
			return getChildren(inputElement);
		}
		public void dispose() {
		}
		public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
		}
	}
	class LabelProvider implements ITableLabelProvider {