socket编程实现信道复用技术 java代码

以下是一个简单的 Java 代码示例，用于实现 socket 编程中的信道复用技术：

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.util.Iterator;

public class SocketMultiplexer {
    private Selector selector;
    private ServerSocketChannel serverSocketChannel;

    public void init(int port) throws IOException {
        selector = Selector.open();
        serverSocketChannel = ServerSocketChannel.open();
        serverSocketChannel.configureBlocking(false);
        serverSocketChannel.socket().bind(new InetSocketAddress(port));
        serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);
    }

    public void run() throws IOException {
        while (true) {
            selector.select();
            Iterator<SelectionKey> iterator = selector.selectedKeys().iterator();
            while (iterator.hasNext()) {
                SelectionKey key = iterator.next();
                iterator.remove();

                if (key.isAcceptable()) {
                    accept(key);
                } else if (key.isReadable()) {
                    read(key);
                }
            }
        }
    }

    private void accept(SelectionKey key) throws IOException {
        ServerSocketChannel serverSocketChannel = (ServerSocketChannel) key.channel();
        SocketChannel socketChannel = serverSocketChannel.accept();
        socketChannel.configureBlocking(false);
        socketChannel.register(selector, SelectionKey.OP_READ);
    }

    private void read(SelectionKey key) throws IOException {
        SocketChannel socketChannel = (SocketChannel) key.channel();
        ByteBuffer buffer = ByteBuffer.allocate(1024);
        int numRead = socketChannel.read(buffer);
        if (numRead == -1) {
            socketChannel.close();
            key.cancel();
            return;
        }
        byte[] data = new byte[numRead];
        System.arraycopy(buffer.array(), 0, data, 0, numRead);
        System.out.println("Received: " + new String(data));
    }

    public static void main(String[] args) throws IOException {
        SocketMultiplexer multiplexer = new SocketMultiplexer();
        multiplexer.init(8080);
        multiplexer.run();
    }
}

这个示例代码实现了一个简单的服务器，监听本地的 8080 端口，并使用 selector 实现了信道复用。当有新的连接请求时，会调用 accept() 方法接受连接，并将新的 SocketChannel 注册到 selector 中，以便后续处理读写事件。当有数据可读时，会调用 read() 方法读取数据，并输出到控制台。

希望这个示例能够帮助你理解 socket 编程中的信道复用技术。