/*

 * Copyright 2001-2003 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package sun.nio.ch;

import java.io.IOException;

import java.nio.channels.ClosedChannelException;

import java.nio.channels.FileLock;

import java.nio.channels.FileChannel;

public class FileLockImpl

    extends FileLock

{

    boolean valid;

    FileLockImpl(FileChannel channel, long position, long size, boolean shared)

    {

        super(channel, position, size, shared);

        this.valid = true;

    }

    public synchronized boolean isValid() {

        return valid;

    }

    synchronized void invalidate() {

        valid = false;

    }

    public synchronized void release() throws IOException {

        if (!channel().isOpen())

            throw new ClosedChannelException();

        if (valid) {

            ((FileChannelImpl)channel()).release(this);

            valid = false;

        }

    }

}