集册 Java实例教程 通过服务器socketchannel的Echo服务器

通过服务器socketchannel的Echo服务器

欢马劈雪     最近更新时间:2020-01-02 10:19:05

532
通过ServerSocketChannel的Echo Server

/**来自 
 NowJava.com - 时  代  Java**/

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.io.UnsupportedEncodingException;

import java.net.InetSocketAddress;

import java.net.ServerSocket;

import java.net.Socket;

import java.net.SocketAddress;

import java.nio.ByteBuffer;

import java.nio.channels.Channels;

import java.nio.channels.SelectableChannel;

import java.nio.channels.SelectionKey;

import java.nio.channels.Selector;// 来 自 时 代 J     a    v  a - nowjava.com

import java.nio.channels.ServerSocketChannel;

import java.nio.channels.SocketChannel;

import java.util.Date;

import java.util.Iterator;

import java.util.Set;


public class NioEchoServer extends Thread {


    private static final int PORT_NUMBER = 6000;

    private static final long TIME_OUT = 3000;

    private ServerSocketChannel mServerChannel;

    private Selector mSelector;

    private boolean mLoop;


    ByteBuffer mBuf = ByteBuffer.allocate(8192);


    public NioEchoServer(int port) {

        SocketAddress isa = new InetSocketAddress(port);

        try {

            mServerChannel = ServerSocketChannel.open();

            mServerChannel.configureBlocking(false);

            ServerSocket s = mServerChannel.socket();


            s.bind(isa);

            mSelector = Selector.open();

            mServerChannel.register(mSelector, SelectionKey.OP_ACCEPT);

            mLoop = true;

        } catch (IOException e) {

            e.printStackTrace();

        }

    }


    public void run() {

        System.out.println("Waiting for connection from client.");

        try {

            while (mLoop) {

                int n = mSelector.select(TIME_OUT);

                if (n == 0)

                    continue;


                Set<SelectionKey> keys = mSelector.selectedKeys();

                Iterator<SelectionKey> it = keys.iterator();


                while (it.hasNext()) {

                    SelectionKey key = (SelectionKey) it.next();

                    if (!key.isValid())

                        continue;


                    if (key.isAcceptable()) {

                        acceptData(key);

                    } else if (key.isReadable()) {

                        processData(key);

                    }

                    it.remove();

                }


            }

        } catch (Exception e) {

            e.printStackTrace();

        }

    }


    private void processData(SelectionKey key) throws IOException {

        if (key == null) {

            return;

        }


        SocketChannel channel = (SocketChannel) key.channel();

        mBuf.clear();

        int count = channel.read(mBuf);

        try {

            if (count < 0) {

                Socket socket = channel.socket();

                SocketAddress remoteAddr = socket.getRemoteSocketAddress();

                System.out.println(remoteAddr + " client: is shutdown.");

                channel.close();

                key.cancel();

                return;

            } else {

                mBuf.flip();

                byte[] receivedData = new byte[count];

                System.arraycopy(mBuf.array(), 0, receivedData, 0, count);

                String receivedStr = new String(receivedData);


                echo(channel, receivedStr);

                if (mBuf.remaining() > 0) {

                    key.selector().wakeup();

                }

            }

        } catch (Exception e) {

            e.printStackTrace();

            key.channel().close();

            key.selector().wakeup();

        }


    }


    private void echo(SocketChannel channel, String receivedStr)

            throws IOException {

        mBuf.clear();

        mBuf.put(receivedStr.getBytes());

        mBuf.flip();

        channel.write(mBuf);


        System.out.println("server sends the message : " + receivedStr

                + " at" + new Date());


    }


    private void acceptData(SelectionKey key) throws IOException {

        ServerSocketChannel server = (ServerSocketChannel) key.channel();

        SocketChannel channel = server.accept();

        channel.configureBlocking(false);


        Socket socket = channel.socket();

        SocketAddress remoteAddr = socket.getRemoteSocketAddress();

        System.out.println("Connection opened client:" + remoteAddr);

        channel.register(mSelector, SelectionKey.OP_READ);


    }


    public static void main(String[] args) {

        int port = PORT_NUMBER;

        if (args.length > 0) {

            port = Integer.parseInt(args[0]);

        }


        NioEchoServer server = new NioEchoServer(port);

        server.start();

        try {

            server.join();

        } catch (InterruptedException e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        }

    }


    private void serversocket1() throws IOException {

        Selector selector = Selector.open();

        ServerSocketChannel server = ServerSocketChannel.open();


        ServerSocket socket = server.socket();

        SocketAddress address = new InetSocketAddress(5000);

        socket.bind(address);


        server.configureBlocking(false);

        server.register(selector, SelectionKey.OP_ACCEPT);


        ByteBuffer buf = ByteBuffer.allocate(1024);

        while (true) {

            try {

                selector.select();

            } catch (IOException e) {

            }

            Set<SelectionKey> keys = selector.selectedKeys();

            Iterator<SelectionKey> iter = keys.iterator();

            while (iter.hasNext()) {

                SelectionKey selected = iter.next();


                iter.remove();


                SelectableChannel channel = selected.channel();

                if (channel instanceof ServerSocketChannel) {

                    ServerSocketChannel serverChannel = (ServerSocketChannel) channel;

                    SocketChannel socketChannel = serverChannel.accept();

                    if (socketChannel == null) {

                        continue;

                    }


                    socketChannel.configureBlocking(false);

                    int validOps = socketChannel.validOps();


                    socketChannel.register(selector, validOps);

                } else {

                    SocketChannel socketChannel = (SocketChannel) channel;


                }


            }

        }

    }


    private void serversocket2() throws IOException {

        ServerSocketChannel server = ServerSocketChannel.open();

        server.configureBlocking(true);

        server.socket().bind(new InetSocketAddress(5000));

        while (true) {

            SocketChannel sc = server.accept();

        }

    }


    private void serversocket3() throws IOException {


        Selector selector = Selector.open();

        ServerSocketChannel server = ServerSocketChannel.open();


        ServerSocket socket = server.socket();

        SocketAddress address = new InetSocketAddress(5000);

        socket.bind(address);


        server.configureBlocking(false);

        server.register(selector, SelectionKey.OP_ACCEPT);


        ByteBuffer buf = ByteBuffer.allocate(1024);

        while (true) {

            try {

                selector.select();

            } catch (IOException e) {

            }

            Set<SelectionKey> keys = selector.selectedKeys();

            Iterator<SelectionKey> iter = keys.iterator();

            while (iter.hasNext()) {

                SelectionKey selected = iter.next();


                iter.remove();


                SelectableChannel channel = selected.channel();

                if (channel instanceof ServerSocketChannel) {

                    ServerSocketChannel serverChannel = (ServerSocketChannel) channel;

                    SocketChannel socketChannel = serverChannel.accept();

                    if (socketChannel == null) {

                        continue;

       
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