the reactor pattern and java nio

 需要对JNI的封装。如果要了解对于不同平台的封装,可以通过ZThead库来了解会有更大的意义。这样可以避免对JNI 的干扰。因为JNI涉及到脚本语言java和C/C++交互的知识。

How to Build a Scalable Multiplexed Server With NIO

Reactor Pattern Mapped to NIO
Handle
SelectionKey
Event
SelectionKey.OP_READ, etc
Demultiplexer
Selector
Dispatcher
Selector.select() + iterate Selector.selectedKeys()
Handler
An instance of Runnable or Callable

最简单例子：TestReactor.java

public class TestReactor
{
	
   public static void main(String[] args) throws Exception 
   {
	 
	  //创建serversocketchannel通道.
	  ServerSocketChannel serversocketchannel =ServerSocketChannel.open();
	  //设置非阻塞,异步模式
	  serversocketchannel.configureBlocking(false);
	  //关联的serversocket
	  ServerSocket serversocket = serversocketchannel.socket();
	  SocketAddress endpoint =new InetSocketAddress("127.0.0.1", 8888);
	  //绑定指定的端口
	  serversocket.bind(endpoint);
	  //创建Selector。在Reactor Pattern模式中，相当于Demultiplexer 作用,用来多路复用器
	  Selector sel = Selector.open();
	  //在select中注册链接事件。
	  //在reactor 模式中SelectionKey 相当于event事件。
	  //在SectionKey中存在OP_READ,OP_WRITE,OP_CONNECT,OP_ACCEPT 事件类型。此时与OP_ACCEPT 关联的Channel为ServerSocketChannel
	   SelectionKey selKey = serversocketchannel.register(sel, SelectionKey.OP_ACCEPT);
        while(true)
        {      
        	    //进行阻塞操作,等待事件的到来。返回值在select 模型中表示完成操作的数目
                int selCount = sel.select();
                if(selCount>0)
                {
                	System.out.println("selCount=>>"+selCount);
                }
                //返回可以操作的键集合。在window select 模型中,返回可以操作的fd_set集合
        	    Set<SelectionKey> selKeySet = sel.selectedKeys();
        	    for(SelectionKey key:selKeySet)
        	    {
        	     
        	    	//在SelectionKey中,存在链接可以接受事件,则调用accept()函数就不会存在阻塞现象。
        	    	//select
        	    	if(key.isAcceptable())
        	    	{
        	    		 //获取与SelectionKey.OP_ACCEPT关联的通道。即ServerSocketChannel.
        	    		 ServerSocketChannel serverChannel = (ServerSocketChannel)key.channel();
        	    		 //调用ServerSocketChannel 不会发生阻塞。获取到客户链接
        	    		 SocketChannel socketchannel = serverChannel.accept();
        	    		 //设置阻塞模式
        	    		 socketchannel.configureBlocking(false);
        	    		 //关联SocketChannel的读和写事件
        	    		 socketchannel.register(sel, SelectionKey.OP_READ|SelectionKey.OP_WRITE);
        	    		 //同时可以在SelectionKey中关联其他对象。在Select 模式中，Selectionkey 相当于Completionkey参数
        	    	}
        	    	if(key.isWritable())
        	    	{
        	    		 SocketChannel socketchannel = (SocketChannel)key.channel();
        	    		 ByteBuffer src =ByteBuffer.allocate(100);
        	    		 src.putInt(100);
        	    		 src.flip();
						 socketchannel.write(src);
						 //关联SocketChannel的读和写事件
        	    		 socketchannel.register(sel, SelectionKey.OP_READ);
        	    		 //同时可以在SelectionKey中关联其他对象。在Select 模式中，Selectionkey 相当于Completionkey参数
        	    		
        	    	}
        	    	if(key.isReadable())
        	    	{
        	    		 SocketChannel socketchannel = (SocketChannel)key.channel();
        	    		 InetSocketAddress remote = (InetSocketAddress)socketchannel.getRemoteAddress();
        	    		 String remotestring = remote.getHostString()+remote.getPort();
        	    		 //关联SocketChannel的读和写事件
        	    		 socketchannel.register(sel, SelectionKey.OP_WRITE);
        	    		 //同时可以在SelectionKey中关联其他对象。在Select 模式中，Selectionkey 相当于Completionkey参数
        	    	}
        	    	selKeySet.remove(key);
        	    }
        	   
        }
        
	  
   }
}

the reactor pattern and java nio

原文：http://blog.csdn.net/sunning9001/article/details/46839377