JavaSE聊天室小项目

使用TCP编程实现客户端和服务器端的不断交互

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Scanner;
/**
 *   客户端
 * */
public class ChatRoomClient {
    public static void main(String[] args) {
        try {
            //创建Socket对象
            Socket s = new Socket("127.0.0.1",12345);
            //获取客户端通道的输出和输入流
            InputStream in = s.getInputStream();
            OutputStream out = s.getOutputStream();
            //创建键盘录入对象
            Scanner sc = new  Scanner(System.in);
            //客户端不断的发送消息
            while(true) {
                System.out.println("请输入消息：");
                String msg = sc.nextLine();
                //使用输出流发送过去
                out.write(msg.getBytes());
                //客户端读取服务器发送的消息
                byte [] bys = new byte [1024];
                int len = in.read(bys);
                String msgStr = new String(bys, 0, len);
                System.out.println(msgStr);
            }
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;
/**
 * 服务器端
 * */
public class ChatRoomServer {
    public static void main(String[] args) {
        try {
            //创建服务器端Socket对象
            ServerSocket ss = new ServerSocket(12345);
            //监听客户端
            Socket s = ss.accept();
            //获取服务器端通道的输出和输入流
            InputStream in = s.getInputStream();
            OutputStream out = s.getOutputStream();
            //创建键盘录入对象
            Scanner sc = new  Scanner(System.in);
            //服务器端不断的读取消息和回复消息
            while(true) {
                //读消息
                byte [] bys = new byte [1024];
                int len = in.read(bys);
                String msg = new String(bys, 0, len);
                System.out.println(msg);
                //回复消息
                System.out.println("请回复消息：");
                String msgStr = sc.nextLine();
                out.write(msgStr.getBytes());
            }    
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

这样做有问题，客户端和服务器端的读发消息都在一个线程，可能会出现互相等待的问题

改进：将读消息放在子线程里面（规定）

客户端

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Scanner;
/**
 * 客户端
 * @author dreamer_96
 */
public class ChatRoomClient {
    public static void main(String[] args) {
        try {
            //创建Socket对象
            Socket s = new Socket("127.0.0.1",12345);
            //获取客户端通道的输出和输入流
            InputStream in = s.getInputStream();
            OutputStream out = s.getOutputStream();
            //创建键盘录入对象
            Scanner sc = new  Scanner(System.in);
            //开启读消息子线程
            ClientThread ct = new ClientThread(in);
            ct.start();
            //客户端不断的发送消息
            while(true) {
                System.out.println("请输入消息：");
                String msg = sc.nextLine();
                //使用输出流发送过去
                out.write(msg.getBytes());
            }    
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

客户端读消息子线程

import java.io.IOException;
import java.io.InputStream;
/**
 * 客户端读取消息的子线程
 * @author dreamer_96
 */
public class ClientThread extends Thread {
    private InputStream in ;
    public ClientThread(InputStream in) {
        this.in = in;
    }
    @Override
    public void run() {
        try {
            while(true) {
                //客户端不断读取服务器发送的消息
                byte [] bys = new byte [1024];
                int len = in.read(bys);
                String msgStr = new String(bys, 0, len);
                System.out.println(msgStr);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

服务器端

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;
/**
 * 服务器端
 * @author dreamer_96
 */
public class ChatRoomServer {
    public static void main(String[] args) {
        try {
            //创建服务器端Socket对象
            ServerSocket ss = new ServerSocket(12345);
            //监听客户端
            Socket s = ss.accept();
            //获取服务器端通道的输出和输入流
            InputStream in = s.getInputStream();
            OutputStream out = s.getOutputStream();
            //创建键盘录入对象
            Scanner sc = new  Scanner(System.in);
            //开启子线程
            ServerThread st = new ServerThread(in);
            st.start();
            //服务器端不断的读取消息和回复消息
            while(true) {
                //回复消息
                System.out.println("请回复消息：");
                String msgStr = sc.nextLine();
                out.write(msgStr.getBytes());
            }    
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

服务器端读消息子线程

import java.io.IOException;
import java.io.InputStream;
/**
 * 服务器端读取消息的子线程
 * @author dreamer_96
 */
public class ServerThread extends Thread {
    private InputStream in;
    public ServerThread(InputStream in) {
        this.in= in ;
    }
    @Override
    public void run() {
        try {
            while(true) {
                //读取客户端发送的消息
                byte [] bys = new byte [1024];
                int len = in.read(bys);
                String msg = new String(bys, 0, len);
                System.out.println(msg);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }    
}

使用ArrayList集合存储Socket对象

服务器端

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.Scanner;
/**
 * 服务器端
 * @author dreamer_96
 */
public class ChatRoomServer {
    public static void main(String[] args) {
        try {
            //创建服务器端Socket对象
            ServerSocket ss = new ServerSocket(12345);
            //创建ArrayList集合;分别保存每个通道内的Socket对象
            ArrayList<Socket> list = new ArrayList<Socket>();
            System.out.println("等待客户端连接，请稍后....");
            int i = 1;
            while(true) {
                //监听客户端
                Socket s = ss.accept();
                System.out.println("第"+(i++)+"个客户端已连接");
                //服务器一监听到客户端，就跳添加到集合中
                list.add(s);
                //获取服务器端通道的输出和输入流
                InputStream in = s.getInputStream();
                OutputStream out = s.getOutputStream();
                //开启子线程
            //    ServerThread st = new ServerThread(in);
                ServerThread st = new ServerThread(s,list);
                st.start();
            }
            /*//创建键盘录入对象
            Scanner sc = new  Scanner(System.in);
            //服务器端不断的读取消息和回复消息
            while(true) {
                //回复消息
                System.out.println("请回复消息：");
                String msgStr = sc.nextLine();
                out.write(msgStr.getBytes());
            }*/    
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

服务器端读消息子线程

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
import java.util.ArrayList;
/**
 * 服务器端读取消息的子线程
 * @author dreamer_96
 */
public class ServerThread extends Thread {
    /*private InputStream in;
    public ServerThread(InputStream in) {
        this.in= in ;
    }*/
    private Socket s;
    private ArrayList<Socket> list;
    public ServerThread(Socket s, ArrayList<Socket> list) {
        this.s = s;
        this.list = list;
    }
    @Override
    public void run() {
        try {
            //获取通道内的输入输出流        
            InputStream in = s.getInputStream();
            OutputStream out = s.getOutputStream();
            while(true) {
                //读取客户端发送的消息
                byte [] bys = new byte [1024];
                int len = in.read(bys);
                String msg = new String(bys, 0, len);
                //msg现在的格式：  接收者:消息内容:发送者
                System.out.println(msg);
                //将消息拆分
                String[] msgs = msg.split(":");
                Socket socket = list.get(Integer.parseInt(msgs[0]));
                //获取输出流，写过去
                OutputStream os = socket.getOutputStream();
                os.write((msgs[2]+"对你说"+msgs[1]).getBytes());
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }    
}