NIO学习笔记（4）-- 【练习】NIO聊天工具

通过NIO的学习，自己简单写了一个，C/S架构的聊天工具。

Server端：

1.接受客户端Channel。

2.记录客户端集合clients。利用channel进行区分客户端，后续可以添加一个ID。

3.客户端通过遍历clients，对除发送者以外的所有客户端通讯。

Client端：

1.发送请求。

2.接收内容

3.获取控制台内容，并发送

待解决问题：

由于获取控制台数据的流，System.in是阻塞的IO：

ReadableByteChannel in=Channels.newChannel(System.in);
ByteBuffer buffer = ByteBuffer.allocate(1024);
in.read(buffer);//这里会阻塞

所以每次接收消息的话，并需控制台触发一下，不知道有没有好的方法，还请知道的大牛指导下，谢谢

以下是代码：

public class NioServer {
	private static Set<SocketChannel> clients=new HashSet<SocketChannel>();
	
	public static void main(String[] args) {
		ServerSocketChannel serverChannel;
		Selector selector;
		
		try{
			//服务端的准备
			serverChannel= ServerSocketChannel.open();
			ServerSocket serverSocket=serverChannel.socket();
			serverSocket.bind(new InetSocketAddress(12345));
			serverChannel.configureBlocking(false);
			selector=Selector.open();
			serverChannel.register(selector, SelectionKey.OP_ACCEPT);
		} catch (IOException e){
			e.printStackTrace();
			return;
		}
		
		while(true){
			try {
				selector.select();
				System.out.println("======select========");
			} catch (IOException e) {
				e.printStackTrace();
				break;
			}
			Iterator<SelectionKey> iterator = selector.selectedKeys().iterator();
			
			while(iterator.hasNext()){
				SelectionKey key=iterator.next();
				iterator.remove();
				
				try {
					if(key.isAcceptable()){
						System.out.println("=============accept============");
						ServerSocketChannel server = (ServerSocketChannel) key.channel();
						SocketChannel client=server.accept();//接受客户端的请求
						client.configureBlocking(false);//客户端 服务端 全都设置为 非阻塞
						
						clients.add(client);
						client.register(key.selector(), SelectionKey.OP_READ);
					}
					if(key.isReadable()){
						System.out.println("=============read==============="+clients);
						SocketChannel client=(SocketChannel) key.channel();
						ByteBuffer buffer=ByteBuffer.allocate(1024);
						if(client.read(buffer)>0){
							Iterator<SocketChannel> it=clients.iterator();
							while(it.hasNext()){
								SocketChannel other=it.next();
								if(other != client){
									buffer.flip();
									other.write(buffer);
								}
							}
						}
						
						key.interestOps(SelectionKey.OP_READ);
					}
				} catch (IOException e) {
					e.printStackTrace();
					
				}
			}
		}
	}
}

private String name="A";
	
	public void execute(){
		try {
			SocketChannel client = SocketChannel.open();
			Selector selector = Selector.open();
			
			client.configureBlocking(false);
			client.connect(new InetSocketAddress("127.0.0.1", 12345));
			//注册监听Connect
			client.register(selector, SelectionKey.OP_CONNECT,name);
			while(true){
				int n = selector.select();
				if(n==0){
					continue;
				}
				Iterator<SelectionKey> iterator=selector.selectedKeys().iterator();
				while(iterator.hasNext()){
					SelectionKey key=iterator.next();
					iterator.remove();
					
					if(key.isConnectable() && client.finishConnect()){
						System.out.println("[client]:连接成功");
						ByteBuffer buffer = ByteBuffer.allocate(1024);
						buffer.put(name.getBytes());
						buffer.flip();
						client.write(buffer);
						
						key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
					}
					if(key.isReadable()){
						System.out.println("[client]:开始接受");
						ByteBuffer buffer = ByteBuffer.allocate(1024);
						WritableByteChannel out = Channels.newChannel(System.out);
						while(client.read(buffer)>0){
							System.out.println("==============");
							buffer.flip();
							out.write(buffer);
						}
						key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
					}
					if(key.isWritable()){
						ReadableByteChannel in=Channels.newChannel(System.in);
						ByteBuffer buffer = ByteBuffer.allocate(1024);
						
						if(in.read(buffer)>0){
							buffer.flip();
							SocketChannel channel = (SocketChannel) key.channel();
							channel.write(buffer);
							buffer.clear();
						}
						key.interestOps(SelectionKey.OP_READ);
					}
				}
			}
		} catch (IOException e) {
			e.printStackTrace();
		}
		
	}