Java Socket编程 实现私聊和群聊

####代码

public class ServerSocket02 {
    private static CopyOnWriteArrayList list=new CopyOnWriteArrayList();
    public static void main(String[] args) throws IOException {
        ServerSocket serverSocket = new ServerSocket(4444);
        System.out.println("服务端创建成功");
        boolean isRunning=true;
        while (isRunning){
            Socket accept = serverSocket.accept();
            Server02 server02 = new Server02(accept);
            list.add(server02);
            new Thread(server02).start();
        }
    }
    static class Server02 implements  Runnable{
        private Socket socket;
        private DataOutputStream out=null;
        private DataInputStream in=null;
        public String name;
        private boolean isRunning=true;
        public Server02(Socket socket){
            this.socket=socket;
            try {
                out=new DataOutputStream(socket.getOutputStream());
                in=new DataInputStream(socket.getInputStream());
                name=receive();
                System.out.println(name+"已连接");
                otherSend(name+"已上线",true);
                send("欢迎你"+name);
            }catch (IOException e){
                closes();
                //e.printStackTrace();
            }
        }
        @Override
        public void run() {
            while (isRunning){
                String receive = receive();
                if(!receive.equals("")) {//判断接收的内容是否为空
                    otherSend(receive,false);
                }
            }
        }
        //接收
        public String receive(){
            String mes="";
            try {
                mes=in.readUTF();
                return mes;
            } catch (IOException e) {
                closes();
               // e.printStackTrace();
            }
            return mes;
        }
        //发送
        public void send(String mes){
            try {
                out.writeUTF(mes);
            } catch (IOException e) {
                closes();
               // e.printStackTrace();
            }
        }
        //群发
        public void otherSend(String mes,boolean f){

            //封装判断是否为私聊
            boolean isPrivate = mes.startsWith("@");
            if(isPrivate){ //判断是否为私聊
                int ind = mes.indexOf("~");
                String name=mes.substring(1,ind);
                mes=mes.substring(ind+1);
                for (Server02 server02 : list) {
                    if(server02.name.equals(name)){
                        server02.send(this.name+"@你说："+mes);
                        break;
                    }
                }
            }else {
                if(f){
                    mes="系统消息"+mes;
                }else {
                    mes=this.name+":"+mes;
                }
                for (Server02 server02 : list) {
                    if(this==server02){
                        continue;
                    }
                    server02.send(mes);
                }
            }
        }
        public void closes(){
            isRunning=false;
            Utiles.closes(in,out,socket);
            System.out.println(this.name+"已退出连接");
            otherSend(this.name+"离开了",true);
            list.remove(this);
        }
    }
}

public class Client01 {
    public static void main(String[] args) throws IOException {
        System.out.print("请输入姓名：");
        String name=new BufferedReader(new InputStreamReader(System.in)).readLine();
        Socket socket = new Socket("localhost", 4444);
       // socket.getOutputStream().write(name.getBytes());
        //创建写出数据的线程
            new Thread(()->{
                OutputStream outputStream = null;
                DataOutputStream dataOutputStream=null;
                try {
                    outputStream = socket.getOutputStream();
                    dataOutputStream = new DataOutputStream(outputStream);
                    dataOutputStream.writeUTF(name);//发送姓名
                } catch (IOException e) {
                    e.printStackTrace();
                }
                try {
                    while (true) {
                        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
                        dataOutputStream.writeUTF(reader.readLine());
                    }
                } catch (IOException e) {
                    //关闭资源  自定义一个工具类 //Closeable//所有需要释放的都实现了该接口
                    Utiles.closes(dataOutputStream,outputStream,socket);
                    e.printStackTrace();
                }
            }).start();
            //创建读取数据的线程
            new Thread(()->{
                DataInputStream inputStream = null;
                try {
                    inputStream = new DataInputStream(socket.getInputStream());
                } catch (IOException e) {
                    e.printStackTrace();
                }
                try {
                    while (true) {
                        System.out.println(inputStream.readUTF());
                    }
                } catch (IOException e) {
                    Utiles.closes(inputStream,socket);
                    e.printStackTrace();
                }
            }).start();
    }
}

public class Utiles {
    public static void closes(Closeable ... closeables){
        for (Closeable closeable : closeables) {
            try {
                System.out.println("已关闭资源");
                closeable.close();
            }catch (IOException i){
                i.printStackTrace();
            }
        }
    }
}