public class ServerThread extends  Thread {
    //需要處理的socket
    private Socket socket;
    //該線程對應的用戶信息
    private User user;
    //新建讀取信息緩存區
    public BufferedReader bufferedReader;
    //新建寫入字符流
    public PrintWriter printWriter;

    //通過構造方法，初始化socket
    public ServerThread(Socket socket){
        this.socket=socket;
    }
    //該線程運行內容
    public void run(){

        try{
            //獲得輸入流，將數據載入緩存區
            bufferedReader=new BufferedReader(new InputStreamReader(socket.getInputStream()));
            //輸出流,true為開啟自動釋放flush
            printWriter=new PrintWriter(socket.getOutputStream(),true);
            //歡迎詞
            sentMessage(printWriter,"歡迎登入聊天室"+",當前在線用戶個數："+ServerSide.clinets.size());
            System.out.println("-----------------進入用戶登錄階段-----------------");
            //進行登錄操作
            user=Login(bufferedReader,printWriter);
            //登錄成功之後，再加入到線程列表中
            ServerSide.clinets.add(this);
            System.out.println("-----------------進入用戶信息轉發階段-----------------");
            //登錄完成後，進入該用戶信息轉發階段
            forwardMessage(bufferedReader,user);
            System.out.println("-----------------進入用戶退出階段-----------------");

            //sentMessage(printWriter,"退出成功！");
            bufferedReader.close();
            printWriter.close();
            this.socket.close();
            //從列表刪除該線程
            ServerSide.clinets.remove(this);
        }catch (Exception e){
            e.printStackTrace();
        }
    }


    /**
     * 信息轉發階段
     * @param bufferedReader
     * @return
     */
    public void forwardMessage(BufferedReader bufferedReader,User user){
        String clinetMessage=readMessage(bufferedReader);
        //Config.ExitCode為退出指令，為‘886’
        while (!Config.ExitCode.equals(clinetMessage)){
            for(int i=0;i<ServerSide.clinets.size();i++){
                ServerThread serverThread=ServerSide.clinets.get(i);
                //自身不需要發送數據
                if(serverThread!=this){
                    //獲得對應的printWriter，發送短信
                    sentMessage(serverThread.printWriter,user.getName()+":"+clinetMessage);
                }
            }
            //等待下條數據
            clinetMessage=readMessage(bufferedReader);
        }
    }

    /**
     * 初始化登錄環節
     * @param bufferedReader
     * @param printWriter
     * @return
     */
    public User Login(BufferedReader bufferedReader,PrintWriter printWriter){
        User user=new User();
        Boolean flag=false;
        while (!flag){
            sentMessage(printWriter,"請輸入初始用戶名：");
            String name=readMessage(bufferedReader);
            user.setName(name);
            sentMessage(printWriter,"請輸入初始密碼：");
            String psw=readMessage(bufferedReader);
            user.setPsw(psw);
            //校驗賬號密碼
            flag=checkUser(user);
            //登錄失敗，返回結果
            if(!flag){
                sentMessage(printWriter,Config.LoginErrCode);
            }
        }
        //登錄成功後，設置身份標示
        user.setId(UUID.randomUUID().toString());
        sentMessage(printWriter,Config.LoginSuccessCode);
        System.out.println(user.toString()+",登錄成功！"+",當前在線用戶個數："+ServerSide.clinets.size());
        return user;
    }

    /**
     * 檢查用戶是否正確
     * 這裏固定了兩個用戶
     * @param user
     * @return
     */
    public Boolean checkUser(User user){
        if(("admin".equals(user.getName())&&"123456".equals(user.getPsw()))||
                ("root".equals(user.getName())&&"123456".equals(user.getPsw()))||
                     ("czg".equals(user.getName())&&"123456".equals(user.getPsw()))){
            return true;
        }
        return false;
    }

    /**
     * 讀取信息
     * @param bufferedReader
     */
    public String readMessage(BufferedReader bufferedReader) {
        String clinetMessage="";
        try {
            clinetMessage= bufferedReader.readLine();
            String username=(user==null?"未登錄用戶":user.getName());
            System.out.println(username+"："+clinetMessage);
        }catch (Exception e){
            e.printStackTrace();
        }
        return clinetMessage;
    }

    /**
     * 發送信息
     * @param printWriter
     * @param message
     */
    public void sentMessage(PrintWriter printWriter,String message){
        printWriter.println(message);
        printWriter.flush();
    }
}

　　參考資料鏈接：https://blog.csdn.net/BlueSky_USC/article/details/54414860

public class ServerThread extends  Thread {
    //需要處理的socket
private Socket socket;
    //該線程對應的用戶信息
private User user;
    //新建讀取信息緩存區
public BufferedReader bufferedReader;
    //新建寫入字符流
public PrintWriter printWriter;

    //通過構造方法，初始化socket
public ServerThread(Socket socket){
        this
 
.socket=socket;
    }
    //該線程運行內容
public void run(){

        try{
            //獲得輸入流，將數據載入緩存區
bufferedReader=new BufferedReader(new InputStreamReader(socket.getInputStream()));
            //輸出流,true為開啟自動釋放flush
printWriter=new PrintWriter(socket.getOutputStream(),true);
            //歡迎詞
sentMessage(printWriter,"
 
歡迎登入聊天室"+",當前在線用戶個數："+ServerSide.clinets.size());
            System.out.println("-----------------進入用戶登錄階段-----------------");
            //進行登錄操作
user=Login(bufferedReader,printWriter);
            //登錄成功之後，再加入到線程列表中
ServerSide.clinets.add(this);
            System.out.println("-----------------進入用戶信息轉發階段-----------------");
            //登錄完成後，進入該用戶信息轉發階段
forwardMessage(bufferedReader,user);
            System.out.println("-----------------進入用戶退出階段-----------------");

            //sentMessage(printWriter,"退出成功！");
bufferedReader.close();
            printWriter.close();
            this.socket.close();
            //從列表刪除該線程
ServerSide.clinets.remove(this);
        }catch (Exception e){
            e.printStackTrace();
        }
    }


    /**
     * 信息轉發階段
* @param bufferedReader
* @return
*/
public void forwardMessage(BufferedReader bufferedReader,User user){
        String clinetMessage=readMessage(bufferedReader);
        //Config.ExitCode為退出指令，為‘886’
while (!Config.ExitCode.equals(clinetMessage)){
            for(int i=0;i<ServerSide.clinets.size();i++){
                ServerThread serverThread=ServerSide.clinets.get(i);
                //自身不需要發送數據
if(serverThread!=this){
                    //獲得對應的printWriter，發送短信
sentMessage(serverThread.printWriter,user.getName()+":"+clinetMessage);
                }
            }
            //等待下條數據
clinetMessage=readMessage(bufferedReader);
        }
    }

    /**
     * 初始化登錄環節
* @param bufferedReader
* @param printWriter
* @return
*/
public User Login(BufferedReader bufferedReader,PrintWriter printWriter){
        User user=new User();
        Boolean flag=false;
        while (!flag){
            sentMessage(printWriter,"請輸入初始用戶名：");
            String name=readMessage(bufferedReader);
            user.setName(name);
            sentMessage(printWriter,"請輸入初始密碼：");
            String psw=readMessage(bufferedReader);
            user.setPsw(psw);
            //校驗賬號密碼
flag=checkUser(user);
            //登錄失敗，返回結果
if(!flag){
                sentMessage(printWriter,Config.LoginErrCode);
            }
        }
        //登錄成功後，設置身份標示
user.setId(UUID.randomUUID().toString());
        sentMessage(printWriter,Config.LoginSuccessCode);
        System.out.println(user.toString()+",登錄成功！"+",當前在線用戶個數："+ServerSide.clinets.size());
        return user;
    }

    /**
     * 檢查用戶是否正確
* 這裏固定了兩個用戶
* @param user
* @return
*/
public Boolean checkUser(User user){
        if(("admin".equals(user.getName())&&"123456".equals(user.getPsw()))||
                ("root".equals(user.getName())&&"123456".equals(user.getPsw()))||
                     ("czg".equals(user.getName())&&"123456".equals(user.getPsw()))){
            return true;
        }
        return false;
    }

    /**
     * 讀取信息
* @param bufferedReader
*/
public String readMessage(BufferedReader bufferedReader) {
        String clinetMessage="";
        try {
            clinetMessage= bufferedReader.readLine();
            String username=(user==null?"未登錄用戶":user.getName());
            System.out.println(username+"："+clinetMessage);
        }catch (Exception e){
            e.printStackTrace();
        }
        return clinetMessage;
    }

    /**
     * 發送信息
* @param printWriter
* @param message
*/
public void sentMessage(PrintWriter printWriter,String message){
        printWriter.println(message);
        printWriter.flush();
    }
}

聊天室-服務端線程處理客戶端信息