170407、java基于nio工作方式的socket通信

客户端代码：

/**

 *

 */

package com.bobohe.nio;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.net.InetSocketAddress;

import java.nio.ByteBuffer;

import java.nio.channels.SelectionKey;

import java.nio.channels.Selector;

import java.nio.channels.SocketChannel;

import java.nio.charset.Charset;

/**

 * 实现TCP/IP+NIO 方式的系统间通讯的代码，客户端：

 *

 * @author solo

 */

public class NioClient {

    /**

     * create solo

     * @param args

     * @throws IOException

     */

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

        String host = "127.0.0.1";

        int port = 9527;

        Selector selector = Selector.open();

        SocketChannel clientChannel = SocketChannel.open();

        clientChannel.configureBlocking(false);

        clientChannel.connect(new InetSocketAddress(host, port));

        clientChannel.register(selector, SelectionKey.OP_CONNECT);

        BufferedReader systemIn = new BufferedReader(new InputStreamReader(System.in));

        while (true) {

            if (clientChannel.isConnected()) {

                String command = systemIn.readLine();

                clientChannel.write(Charset.forName("UTF-8").encode(command));

                if (command == null || "quit".equalsIgnoreCase(command)) {

                    System.out.println("Client quit!");

                    systemIn.close();

                    clientChannel.close();

                    selector.close();

                    System.exit(0);

                }

            }

            //最长阻塞10s

            int nKeys = selector.select(10 * 1000);

            if (nKeys > 0) {

                for (SelectionKey selectionKey : selector.selectedKeys()) {

                    if (selectionKey.isConnectable()) {

                        SocketChannel socketChannel = (SocketChannel)selectionKey.channel();

                        socketChannel.configureBlocking(false);

                        socketChannel.register(selector, SelectionKey.OP_READ);

                        socketChannel.finishConnect();

                    } else if (selectionKey.isReadable()) {

                        SocketChannel socketChannel = (SocketChannel)selectionKey.channel();

                        StringBuilder sb = new StringBuilder();

                        ByteBuffer byteBuffer = ByteBuffer.allocate(1024);

                        try {

                            int readBytes = 0;

                            int ret = 0;

                            while ((ret = socketChannel.read(byteBuffer)) > 0) {

                                readBytes += ret;

                                byteBuffer.flip();

                                sb.append(Charset.forName("UTF-8").decode(byteBuffer).toString());

                                byteBuffer.clear();

                            }

                            if (readBytes == 0) {

                                /*

                                 * handle Exception

                                 */

                                System.err.println("handle opposite close Exception");

                                socketChannel.close();

                            }

                        } catch (IOException e) {

                            /*

                             * handle Exception

                             */

                            System.err.println("handle read Exception");

                            socketChannel.close();

                        } finally {

                            byteBuffer.clear();

                        }

                        String message = sb.toString();

                        System.out.println(message);

                    }

                }

                selector.selectedKeys().clear();

            } else {

                /*

                 * handle Exception

                 * 三秒没有响应则打印错误信息

                 */

                System.err.println("handle select timeout Exception");

                clientChannel.close();

            }

        }

    }

}

服务端代码：

/**

 *

 */

package com.bobohe.nio;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.net.InetSocketAddress;

import java.net.ServerSocket;

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;

/**

 * 实现TCP/IP+NIO 方式的系统间通讯的代码，服务器端： SocketChannel和ServerSocketChannel两个关键的类，网络IO

 * 的操作则改为通过ByteBuffer来实现。

 *

 * @author solo

 */

public class NioServer {

    /**

     * create by solo

     *

     * @param args

     * @throws IOException

     */

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

        int port = 9527;

        System.out.println("Server listen on port: " + port);

        Selector selector = Selector.open();

        ServerSocketChannel serverChannel = ServerSocketChannel.open();

        ServerSocket serverSocket = serverChannel.socket();

        serverSocket.bind(new InetSocketAddress(port));

        serverChannel.configureBlocking(false);

        serverChannel.register(selector, SelectionKey.OP_ACCEPT);

        while (true) {

            int nKeys = selector.select();

            if (nKeys > 0) {

                for (SelectionKey selectionKey : selector.selectedKeys()) {

                    if (selectionKey.isAcceptable()) {

                        ServerSocketChannel tempServerChannel = (ServerSocketChannel) selectionKey

                                .channel();

                        SocketChannel socketChannel = tempServerChannel

                                .accept();

                        if (socketChannel == null) {

                            continue;

                        }

                        socketChannel.configureBlocking(false);

                        socketChannel.register(selector, SelectionKey.OP_READ);

                    } else if (selectionKey.isReadable()) {

                        // try { Thread.sleep(5000); } catch

                        // (InterruptedException e) { e.printStackTrace(); }

                        SocketChannel socketChannel = (SocketChannel) selectionKey

                                .channel();

                        StringBuilder sb = new StringBuilder();

                        ByteBuffer byteBuffer = ByteBuffer.allocate(1024);

                        try {

                            int readBytes = 0;

                            int ret = 0;

                            while ((ret = socketChannel.read(byteBuffer)) > 0) {

                                readBytes += ret;

                                byteBuffer.flip();

                                sb.append(Charset.forName("UTF-8")

                                        .decode(byteBuffer).toString());

                                byteBuffer.clear();

                            }

                            if (readBytes == 0) {

                                /*

                                 * handle Exception

                                 */

                                System.err

                                        .println("handle opposite close Exception");

                                socketChannel.close();

                            }

                            String message = sb.toString();

                            System.out.println("client: "

                                    + message);

                            if ("quit".equalsIgnoreCase(message.toString()

                                    .trim())) {

                                System.out.println("Client has been quit!");

                                socketChannel.close();

                            } else if ("serverquit".equalsIgnoreCase(message

                                    .trim())) {

                                System.out.println("Server has been shutdown!");

                                socketChannel.close();

                                serverChannel.close();

                                selector.close();

                                System.exit(0);

                            } else {

                                socketChannel.write(Charset.forName("UTF-8").encode("Server Handler Done!"));

                            }

                        } catch (IOException e) {

                            /*

                             * handle Exception

                             */

                            System.err.println("handle read Exception");

                            socketChannel.close();

                        } finally {

                            byteBuffer.clear();

                        }

                    }

                }

                selector.selectedKeys().clear();

            }

        }

    }

}