NIO-demo

服务端：

package net.test;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.nio.charset.Charset;
import java.util.Iterator;
import java.util.Set;

public class NIOServer {

    public static void main(String[] args) throws IOException {
        // 负责处理客户端连接的selector
        Selector serverSelector = Selector.open();
        // 负责读写数据的selector
        Selector clientSelector = Selector.open();

        new Thread(() -> {
            try {
                ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
                // 绑定端口8001
                serverSocketChannel.socket().bind(new InetSocketAddress(8000));
                // 开启NIO配置
                serverSocketChannel.configureBlocking(false);

                // 将severSocketChannel绑定到serverSelector，并且selector监听新建连接的事件请求
                serverSocketChannel.register(serverSelector, SelectionKey.OP_ACCEPT);

                while (true) {
                    if (serverSelector.select(1) > 0) {
                        System.out.println("serverSelector.select() ... ");
                        Set<SelectionKey> selectionKeys = serverSelector.selectedKeys();
                        Iterator<SelectionKey> iterator = selectionKeys.iterator();
                        while (iterator.hasNext()) {
                            SelectionKey selectionKey = iterator.next();
                            if (selectionKey.isAcceptable()) {
                                try {
                                    ServerSocketChannel channel = (ServerSocketChannel) selectionKey.channel();
                                    SocketChannel socketChannel = channel.accept();
                                    socketChannel.configureBlocking(false);
                                    // 将处理连接读写请求的通道注册到clientSelector
                                    socketChannel.register(clientSelector, SelectionKey.OP_READ);
                                } finally {
                                    iterator.remove();
                                }
                            }
                        }
                    }
                }
            } catch (Exception e) {

            }
        }).start();


        new Thread(() -> {
            try {
                while (true) {
                    if (clientSelector.select(1) > 0) {
                        System.out.println("clientSelector.select() ... ");
                        Set<SelectionKey> selectionKeys = clientSelector.selectedKeys();
                        Iterator<SelectionKey> iterator = selectionKeys.iterator();
                        while (iterator.hasNext()) {
                            SelectionKey selectionKey = iterator.next();
                            if (selectionKey.isReadable()) {
                                try {
                                    SocketChannel socketChannel = (SocketChannel) selectionKey.channel();
                                    ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
                                    socketChannel.read(byteBuffer);
                                    byteBuffer.flip();
                                    System.out.println(Charset.defaultCharset().newDecoder().decode(byteBuffer)
                                            .toString());
                                } finally {
                                    iterator.remove();
                                    selectionKey.interestOps(SelectionKey.OP_READ);
                                }
                            }
                        }
                    }
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }).start();


    }
}