/*

 * Copyright 2008-2009 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.nio.channels.*;

import java.nio.channels.spi.AsynchronousChannelProvider;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.ThreadFactory;

import java.net.ProtocolFamily;

import java.io.IOException;

public class WindowsAsynchronousChannelProvider

    extends AsynchronousChannelProvider

{

    private static volatile Iocp defaultIocp;

    public WindowsAsynchronousChannelProvider() {

        // nothing to do

    }

    private Iocp defaultIocp() throws IOException {

        if (defaultIocp == null) {

            synchronized (WindowsAsynchronousChannelProvider.class) {

                if (defaultIocp == null) {

                    // default thread pool may be shared with AsynchronousFileChannels

                    defaultIocp = new Iocp(this, ThreadPool.getDefault()).start();

                }

            }

        }

        return defaultIocp;

    }

    @Override

    public AsynchronousChannelGroup openAsynchronousChannelGroup(int nThreads, ThreadFactory factory)

        throws IOException

    {

        return new Iocp(this, ThreadPool.create(nThreads, factory)).start();

    }

    @Override

    public AsynchronousChannelGroup openAsynchronousChannelGroup(ExecutorService executor, int initialSize)

        throws IOException

    {

        return new Iocp(this, ThreadPool.wrap(executor, initialSize)).start();

    }

    private Iocp toIocp(AsynchronousChannelGroup group) throws IOException {

        if (group == null) {

            return defaultIocp();

        } else {

            if (!(group instanceof Iocp))

                throw new IllegalChannelGroupException();

            return (Iocp)group;

        }

    }

    @Override

    public AsynchronousServerSocketChannel openAsynchronousServerSocketChannel(AsynchronousChannelGroup group)

        throws IOException

    {

        return new WindowsAsynchronousServerSocketChannelImpl(toIocp(group));

    }

    @Override

    public AsynchronousSocketChannel openAsynchronousSocketChannel(AsynchronousChannelGroup group)

        throws IOException

    {

        return new WindowsAsynchronousSocketChannelImpl(toIocp(group));

    }

    @Override

    public AsynchronousDatagramChannel openAsynchronousDatagramChannel(ProtocolFamily family,

                                                                       AsynchronousChannelGroup group)

        throws IOException

    {

        return new SimpleAsynchronousDatagramChannelImpl(family, toIocp(group));

    }

}