| /******************************************************************************* |
| * Copyright (c) 2000, 2005 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.javaeditor.selectionactions; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.eclipse.jface.util.Assert; |
| import org.eclipse.jface.viewers.ISelectionChangedListener; |
| import org.eclipse.jface.viewers.SelectionChangedEvent; |
| |
| import org.eclipse.jdt.core.ISourceRange; |
| |
| import org.eclipse.jdt.internal.ui.javaeditor.JavaEditor; |
| |
| public class SelectionHistory { |
| |
| private List fHistory; |
| private JavaEditor fEditor; |
| private ISelectionChangedListener fSelectionListener; |
| private int fSelectionChangeListenerCounter; |
| private StructureSelectHistoryAction fHistoryAction; |
| |
| public SelectionHistory(JavaEditor editor) { |
| Assert.isNotNull(editor); |
| fEditor= editor; |
| fHistory= new ArrayList(3); |
| fSelectionListener= new ISelectionChangedListener() { |
| public void selectionChanged(SelectionChangedEvent event) { |
| if (fSelectionChangeListenerCounter == 0) |
| flush(); |
| } |
| }; |
| fEditor.getSelectionProvider().addSelectionChangedListener(fSelectionListener); |
| } |
| |
| public void setHistoryAction(StructureSelectHistoryAction action) { |
| Assert.isNotNull(action); |
| fHistoryAction= action; |
| } |
| |
| public boolean isEmpty() { |
| return fHistory.isEmpty(); |
| } |
| |
| public void remember(ISourceRange range) { |
| fHistory.add(range); |
| fHistoryAction.update(); |
| } |
| |
| public ISourceRange getLast() { |
| if (isEmpty()) |
| return null; |
| int size= fHistory.size(); |
| ISourceRange result= (ISourceRange)fHistory.remove(size - 1); |
| fHistoryAction.update(); |
| return result; |
| } |
| |
| public void flush() { |
| if (fHistory.isEmpty()) |
| return; |
| fHistory.clear(); |
| fHistoryAction.update(); |
| } |
| |
| public void ignoreSelectionChanges() { |
| fSelectionChangeListenerCounter++; |
| } |
| |
| public void listenToSelectionChanges() { |
| fSelectionChangeListenerCounter--; |
| } |
| |
| public void dispose() { |
| fEditor.getSelectionProvider().removeSelectionChangedListener(fSelectionListener); |
| } |
| } |