1 /*
   2  * Copyright (c) 2008, 2009, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.nio.ch;
  27 
  28 import java.nio.channels.*;
  29 import java.nio.channels.spi.AsynchronousChannelProvider;
  30 import java.util.concurrent.ExecutorService;
  31 import java.util.concurrent.ThreadFactory;
  32 import java.io.IOException;
  33 
  34 public class LinuxAsynchronousChannelProvider
  35     extends AsynchronousChannelProvider
  36 {
  37     private static volatile EPollPort defaultPort;
  38 
  39     private EPollPort defaultEventPort() throws IOException {
  40         if (defaultPort == null) {
  41             synchronized (LinuxAsynchronousChannelProvider.class) {
  42                 if (defaultPort == null) {
  43                     defaultPort = new EPollPort(this, ThreadPool.getDefault()).start();
  44                 }
  45             }
  46         }
  47         return defaultPort;
  48     }
  49 
  50     public LinuxAsynchronousChannelProvider() {
  51     }
  52 
  53     @Override
  54     public AsynchronousChannelGroup openAsynchronousChannelGroup(int nThreads, ThreadFactory factory)
  55         throws IOException
  56     {
  57         return new EPollPort(this, ThreadPool.create(nThreads, factory)).start();
  58     }
  59 
  60     @Override
  61     public AsynchronousChannelGroup openAsynchronousChannelGroup(ExecutorService executor, int initialSize)
  62         throws IOException
  63     {
  64         return new EPollPort(this, ThreadPool.wrap(executor, initialSize)).start();
  65     }
  66 
  67     private Port toPort(AsynchronousChannelGroup group) throws IOException {
  68         if (group == null) {
  69             return defaultEventPort();
  70         } else {
  71             if (!(group instanceof EPollPort))
  72                 throw new IllegalChannelGroupException();
  73             return (Port)group;
  74         }
  75     }
  76 
  77     @Override
  78     public AsynchronousServerSocketChannel openAsynchronousServerSocketChannel(AsynchronousChannelGroup group)
  79         throws IOException
  80     {
  81         return new UnixAsynchronousServerSocketChannelImpl(toPort(group));
  82     }
  83 
  84     @Override
  85     public AsynchronousSocketChannel openAsynchronousSocketChannel(AsynchronousChannelGroup group)
  86         throws IOException
  87     {
  88         return new UnixAsynchronousSocketChannelImpl(toPort(group));
  89     }
  90 }