| /******************************************************************************* |
| * Copyright (c) 2000, 2007 IBM Corporation 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: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| |
| package org.eclipse.jdt.internal.ui.viewsupport; |
| |
| import org.eclipse.jface.viewers.Viewer; |
| import org.eclipse.jface.viewers.ViewerFilter; |
| |
| /** |
| * filter with a live cycle |
| */ |
| public abstract class JavaViewerFilter extends ViewerFilter { |
| |
| private int fCount= 0; |
| |
| /** |
| * To be overridden by implement |
| */ |
| protected abstract void initFilter(); |
| |
| protected abstract void freeFilter(); |
| |
| public final void filteringStart() { |
| if (fCount == 0) |
| initFilter(); |
| fCount++; |
| } |
| |
| public final void filteringEnd() { |
| fCount--; |
| if (fCount == 0) |
| freeFilter(); |
| } |
| |
| /* |
| * Overrides method from ViewerFilter |
| */ |
| public Object[] filter(Viewer viewer, Object parent, Object[] elements) { |
| try { |
| filteringStart(); |
| return super.filter(viewer, parent, elements); |
| } finally { |
| filteringEnd(); |
| } |
| } |
| |
| |
| } |