Socket网络编程

客户端：

import java.io.*;
import java.net.Inet4Address;
import java.net.InetSocketAddress;
import java.net.Socket;

public class Client {
    public static void main(String[] args) throws IOException {
        Socket socket = new Socket();
        socket.setSoTimeout(3000);
        socket.connect(new InetSocketAddress(Inet4Address.getLocalHost(), 2000),3000);
        System.out.println("已发起服务器连接，并进入后续流程~");
        System.out.println("客户端信息："+ socket.getLocalAddress()+" P:"+socket.getLocalPort());
        System.out.println("服务器信息："+ socket.getInetAddress()+" P:"+socket.getPort());
        try{
            todo(socket);
        } catch (Exception e) {
            System.out.println("异常关闭");
        }
        socket.close();
        System.out.println("客户端已退出");
    }

    private static void todo(Socket client) throws IOException {
        //构建键盘输入流
        InputStream in = System.in;
        BufferedReader input = new BufferedReader(new InputStreamReader(in));
        //得到Socket输出流，并转换为打印流
        OutputStream outputStream = client.getOutputStream();
        PrintStream socketPrintStream = new PrintStream(outputStream);

        //得到socket输入流，并转换为BufferedReader
        InputStream inputStream = client.getInputStream();
        BufferedReader socketBufferedReader = new BufferedReader(new InputStreamReader(inputStream));
        boolean flag = true;
        do {
            //键盘读取一行
            String str = input.readLine();
            System.out.println("键盘读取的数据："+ str);
            //发送到服务器
            socketPrintStream.println(str);

            //从服务器读取一行
            String echo = socketBufferedReader.readLine();
            if ("bye".equalsIgnoreCase(echo)) {
                flag = false;
            } else {
                System.out.println(echo);
            }
        }while (flag);
        //资源释放
        socketPrintStream.close();
        socketBufferedReader.close();
    }
}

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

public class Server {
    public static void main(String[] args) throws IOException {
        ServerSocket server = new ServerSocket(2000);
        System.out.println("服务器准备就绪");
        System.out.println("服务器信息："+ server.getInetAddress()+" P:"+server.getLocalPort());
        //等待客户端连接
        for (;;) {
            //得到客户端
            Socket client = server.accept();
            //客户端构建异步线程
            ClientHandler clientHandler = new ClientHandler(client);
            //启动线程
            clientHandler.start();
        }

        /*Socket accept = server.accept();
        try {
            //
        } catch (Exception e) {
            e.printStackTrace();
        }*/


    }

    private static void todo(Socket socket) {
        boolean flag = true;
        System.out.println("新客户端连接："+ socket.getInetAddress()+
                " P:"+socket.getPort());
        try {
            //得到打印流，用于数据输出；服务器回送数据使用
            PrintStream socketOutput = new PrintStream(socket.getOutputStream());
            //得到输入流，用于接收数据
            BufferedReader socketInput =  new BufferedReader(new InputStreamReader(socket.getInputStream()));
            do {
                //客户端拿到一条数据
                String str = socketInput.readLine();
                if ("bye".equalsIgnoreCase(str)) {
                    flag = false;
                    socketOutput.println("bye");
                } else {
                    //打印到屏幕，并回送数据长度
                    System.out.println(str);
                    socketOutput.println("回送：" + str.length());
                }
            }while (flag);
            socketInput.close();
            socketOutput.close();
        } catch (Exception e) {
            System.out.println("连接异常断开");
        } finally {
            try {
                socket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        System.out.println("客户端已退出："+socket.getInetAddress()+ " P:" + socket.getPort());
    }

    private static class ClientHandler extends Thread {
        private Socket socket;
        private boolean flag = true;
        ClientHandler(Socket socket) {
            this.socket = socket;
        }

        @Override
        public void run() {
            super.run();
            System.out.println("新客户端连接："+ socket.getInetAddress()+
                    " P:"+socket.getPort());
            try {
                //得到打印流，用于数据输出；服务器回送数据使用
                PrintStream socketOutput = new PrintStream(socket.getOutputStream());
                //得到输入流，用于接收数据
                BufferedReader socketInput =  new BufferedReader(new InputStreamReader(socket.getInputStream()));
                do {
                    //客户端拿到一条数据
                    String str = socketInput.readLine();
                    if ("bye".equalsIgnoreCase(str)) {
                        flag = false;
                        socketOutput.println("bye");
                    } else {
                        //打印到屏幕，并回送数据长度
                        System.out.println(str);
                        socketOutput.println("回送：" + str.length());
                    }
                }while (flag);
                socketInput.close();
                socketOutput.close();
            } catch (Exception e) {
                System.out.println("连接异常断开");
            } finally {
                try {
                    socket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            System.out.println("客户端已退出："+socket.getInetAddress()+ " P:" + socket.getPort());
        }
    }
}