计网课设-网络聊天程序的设计与实现

先在idea使用gradle构建项目，创建Client，Server两个类，如下图

// client.java
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();
        //超时时间
        socket.setSoTimeout(3000);
        //连接本地（客户端），端口2000，超时时间3000ms
        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{
            //发送接收数据 阻塞
            todo(socket);
        }catch (Exception e){
            System.out.println("异常关闭");
        }
        //释放资源
        socket.close();
        System.out.println("客户端已经退出");

    }
    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 并转换成打印流
        OutputStream outputStream =client.getOutputStream();
        PrintStream socketPrintStream =new PrintStream(outputStream);

        //得到Socket输入流 并转换成BufferedReader
        InputStream inputStream = client.getInputStream();
        BufferedReader socketBufferedReader = new BufferedReader(new InputStreamReader(inputStream));

        boolean flag =true;
        while(flag){
            //从键盘读取一行
            String str= input.readLine();
            //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);
            }
        }

        //资源释放
        socketBufferedReader.close();
        socketPrintStream.close();

    }
}

// Server.java
import java.io.*;
import java.net.Inet4Address;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.sql.SQLOutput;

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
        while(true){
            //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();
        }


    }
    /*
    客户端消息处理
     */
    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;
                        //回送
                        socketOutput.println("bye");
                    }else{
                        //打印到屏幕上 并回送数据长度
                        System.out.println(str);
                        socketOutput.println("回送："+str.length());
                    }
                }while(flag);

                //释放资源
                socketInput.close();
                socketOutput.close();

            }catch (Exception e){
               System.out.println("连接异常断开");
            }finally {
                //连接关闭
                try {
                    socket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
           System.out.println("客户端已退出"+socket.getInetAddress()+"P:"+socket.getPort());
        }
    }
}

点击 构建项目 ,在生成的.class文件中打开文件管理器，打开两个终端（git bush here），最终效果如下