| /******************************************************************************* |
| * Copyright (c) 2004, 2017 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| * * Andrei Loskutov - bug 44735 |
| *******************************************************************************/ |
| package org.eclipse.update.internal.configurator; |
| |
| import java.io.*; |
| import java.nio.channels.FileLock; |
| import java.nio.channels.OverlappingFileLockException; |
| |
| /** |
| * Internal class. |
| */ |
| public class Locker_JavaNio implements Locker { |
| private File lockFile; |
| private RandomAccessFile raf; |
| private FileLock fileLock; |
| |
| public Locker_JavaNio(File lockFile) { |
| this.lockFile = lockFile; |
| } |
| |
| @Override |
| public synchronized boolean lock() throws IOException { |
| raf = new RandomAccessFile(lockFile, "rw"); //$NON-NLS-1$ |
| try{ |
| /* |
| * fix for bug http://bugs.sun.com/view_bug.do?bug_id=6628575 and |
| * https://bugs.eclipse.org/bugs/show_bug.cgi?id=44735#c17 |
| */ |
| fileLock = raf.getChannel().tryLock(0, 1, false); |
| } catch(OverlappingFileLockException e) { |
| fileLock = null; |
| } finally { |
| if (fileLock != null) |
| return true; |
| raf.close(); |
| raf = null; |
| } |
| return false; |
| } |
| |
| @Override |
| public synchronized void release() { |
| if (fileLock != null) { |
| try { |
| fileLock.release(); |
| } catch (IOException e) { |
| //don't complain, we're making a best effort to clean up |
| } |
| fileLock = null; |
| } |
| if (raf != null) { |
| try { |
| raf.close(); |
| } catch (IOException e) { |
| //don't complain, we're making a best effort to clean up |
| } |
| raf = null; |
| } |
| if (lockFile != null) { |
| lockFile.delete(); |
| lockFile = null; |
| } |
| } |
| } |