服務端代碼：

public class MyServer {
    private ServerSocket serverSocket;

    public MyServer() {
        try {
            // 設置你服務器監聽的端口為10000，用戶能使用的端口為1025-65535
            serverSocket = new ServerSocket(10001);
        } catch (IOException e) {
            // 捕獲異常，不懂的話好好看java，
            e.printStackTrace();
        }
        
 
// 創建新的監聽主線程，這個線程創建ServerSocket監聽
        new Thread(new Runnable() {
            public void run() {
                while (true) {
                    Socket socket = null;
                    try {
                        socket = serverSocket.accept();
                        // 當監聽到了客戶端連接後，創建新線程傳輸數據，這樣可以實現多個客戶端同時訪問
 

                        new Thread(new SocketHandler(socket)).start();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            }
        }).start();
    }

    class SocketHandler implements Runnable {
        private
 
 Socket socket;
        private BufferedReader reader;
        private PrintWriter writer;

        SocketHandler(Socket socket) {
            try {
                this.socket = socket;
                reader = new BufferedReader(new InputStreamReader(
                        this.socket.getInputStream(), "GB2312"));
                writer = new PrintWriter(socket.getOutputStream(), true);
                writer.println("-------welcome---------");
                writer.println("-------welcome---------");
                writer.println("-------welcome---------");
            } catch (IOException e) {
                e.printStackTrace();
            }

        }

        // 這裏是覆蓋實現接口Runnable裏的run（）
        public void run() {
            try {
                // 讀取數據，這裏只能讀取一行String
                String line = reader.readLine();
                System.out.println(line);
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                // 最後要關閉Socket
                try {
                    if (socket != null)
                        socket.close();
                    if (reader != null)
                        reader.close();
                    if (writer != null)
                        writer.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    public static void main(String[] args) {
        new MyServer();
    }

}

客戶端代碼：

public class SocketClientDemo implements Runnable {
    private Socket socket;
    BufferedReader reader;
    private PrintWriter writer;

    public SocketClientDemo() {
        try {
            // 127.0.0.1表示本機IP，10000為服務器Socket設置的端口
            socket = new Socket("127.0.0.1", 10001);
            reader = new BufferedReader(new InputStreamReader(
                    socket.getInputStream(), "GB2312"));
            writer = new PrintWriter(socket.getOutputStream(), true);
            writer.println("working.............");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void run() {
        try {
            // 這裏就可以讀取所有行String
            String line, buffer = "";
            while (!((line = reader.readLine()) == null))
                buffer += line;
            System.out.println(buffer);
        } catch (IOException e) {
            e.printStackTrace();
            System.out.println("problem");
        } finally {
            // 最後關閉Socket
            try {
                if (socket != null)
                    socket.close();
                if (reader != null)
                    reader.close();
                if (writer != null)
                    writer.close();
            } catch (IOException e) {
                e.printStackTrace();
            }

        }

    }

    public static void main(String[] args) {
        new Thread(new SocketClientDemo()).start();

    }

}

Socket簡單通信