socket编程

# bio 

import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;

public class SocketServer {

    public static void main(String[] args) throws Exception{
        ServerSocket serverSocket = new ServerSocket(9000);
        while (true) {
            System.out.println("Start to accept.");
            Socket socket = serverSocket.accept();
            new Thread(() -> {
                try {
                    handler(socket);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }).start();
        }
    }

    public static void handler(Socket socket) throws IOException{
        byte[] bytes = new byte[1024];
        int read = socket.getInputStream().read(bytes);
        if (read != -1) {
            System.out.println(new String(bytes, 0, read));
        }
    }
}

 

# nio
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.util.*;

public class SocketServer {

    private static final Set<SocketChannel> socketChannels = new HashSet<>();
    public static void main(String[] args) throws Exception{
        ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
        serverSocketChannel.socket().bind(new InetSocketAddress(9000));
        serverSocketChannel.configureBlocking(false);

        while (true) {
            SocketChannel socketChannel = serverSocketChannel.accept();
            if (socketChannel != null) {
                socketChannel.configureBlocking(false);
                socketChannels.add(socketChannel);
            }
            Iterator iterator = socketChannels.iterator();
            while (iterator.hasNext()) {
                SocketChannel socketChannel1 = (SocketChannel) iterator.next();
                ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
                int len = socketChannel1.read(byteBuffer);
                if (len > 0) {
                    System.out.println(new String(byteBuffer.array()));
                }
                if (len == -1){
                    socketChannels.remove(socketChannel1);
                }
            }
        }
    }
}

 

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;

public class NioServer {
    public static void test() throws IOException {
        Selector selector = Selector.open();

        ServerSocketChannel ssChannel = ServerSocketChannel.open();
        ssChannel.configureBlocking(false);
        ssChannel.socket().bind(new InetSocketAddress(9000));
        ssChannel.register(selector, SelectionKey.OP_ACCEPT);

        while (true) {
            if (selector.select() > 0) {
                for (SelectionKey selectionKey : selector.selectedKeys()) {
                    if (selectionKey.isAcceptable()) {
                        ServerSocketChannel channel = (ServerSocketChannel) selectionKey.channel();
                        SocketChannel socketChannel = channel.accept();
                        socketChannel.configureBlocking(false);
                        socketChannel.register(selector, SelectionKey.OP_READ);
                    } else if (selectionKey.isReadable()) {
                        SocketChannel socketChannel = (SocketChannel) selectionKey.channel();
                        ByteBuffer byteBuffer = ByteBuffer.allocate(128);
                        int len = socketChannel.read(byteBuffer);

                        if (len > 0) {

                            System.out.println(new String(byteBuffer.array()));
                        }
                    }
                    selector.selectedKeys().remove(selectionKey);
                }
            }
        }
    }


    public static void main(String[] args) throws IOException {
        test();
    }
}

 

 

import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

public class NioServer3 {

    private static final Set<SocketChannel> socketChannels = new HashSet<>();

    public static void main(String[] args) throws Exception{
        ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
        serverSocketChannel.socket().bind(new InetSocketAddress(9000));
        serverSocketChannel.configureBlocking(false);


        while (true) {
            SocketChannel socketChannel = serverSocketChannel.accept();
            if (socketChannel != null) {
                socketChannel.configureBlocking(false);
                socketChannels.add(socketChannel);
            }
            Iterator iterator = socketChannels.iterator();
            while (iterator.hasNext()) {
                SocketChannel socketChannel1 = (SocketChannel) iterator.next();
                ByteBuffer byteBuffer = ByteBuffer.allocate(128);
                int size = socketChannel1.read(byteBuffer);
                if (size > 0) {
                    byte[] bytes = new byte[byteBuffer.position()];
                    byteBuffer.flip();
                    byteBuffer.get(bytes, 0, bytes.length);
                    System.out.println(new String(bytes));
                } else if (size < 0){
                    socketChannels.remove(socketChannel1);
                }
            }
        }
    }
}