TCP通信学习 服务端没有响应

用Socket实现了TCP的聊天室的简单模型，
服务器端有两个类：TCPListener是用来监听客户端的连接请求的，并且新起一个线程用来不断的读取socket中的数据并且发送给所有已经建立连接的客户；TCPConnection就是这个读写的线程
客户端有两个类：TCPClient是用来发送连接请求的，并且监听键盘输入的聊天内容并写进socket，每次连接新起一个线程用来不断读取socket里返回的其他用户的聊天内容；TCPClientThread就是这个线程

先运行TCPListener后，再运行TCPClient，问题就是：一个客户端输入内容后，服务器端用来不断读取数据的线程并没有反映，也就是黑体的代码没有执行，其他客户端也没有收到服务器端返回的这个客户端的聊天信息。

TCPListener 

public class TCPListener {

	

	public static List<Socket> sockets = Collections.synchronizedList(new ArrayList<Socket>());

	

	public static void main(String[] args) throws IOException {

		ServerSocket server = new ServerSocket(3003);

		while(true){

			Socket socket = server.accept();

			sockets.add(socket);

			new Thread(new TCPConnection(socket)).start();

		}

	}

}



TCPConnection 

public class TCPConnection implements Runnable{



	private Socket socket = null;

	

	private BufferedReader input = null;

	

	public TCPConnection(Socket socket){

		this.socket = socket;

		try {

			input = new BufferedReader(new InputStreamReader(this.socket.getInputStream()));



		} catch (IOException e) {

			e.printStackTrace();

		}

	}

	

	@Override

	public void run() {

		String content = null;

		try {

			while((content = (input.readLine())) != null){

				System.out.println(“不断读取socket中的数据的这段代码没有被执行”);

				for(Socket target : TCPListener.sockets){

					BufferedWriter output = new BufferedWriter(new OutputStreamWriter(target.getOutputStream()));

					output.write((content + " from server"));

					System.out.println(content + " from server");

//					output.flush();

				}

			}

		} catch (IOException e) {

			TCPListener.sockets.remove(socket);

			System.out.println("A client has exited because of unexpected errors");

			e.printStackTrace();

		}

	}

}



TCPClient 

public class TCPClient {

	

	public static void main(String[] args) {

		try {

			Socket socket = new Socket("127.0.0.1", 3003);

			new Thread(new TCPClientThread(socket)).start();



			PrintWriter writer = new PrintWriter(new OutputStreamWriter(socket.getOutputStream()));

			String content = null;

			BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));

			while((content = reader.readLine()) != null){

				writer.println(content);

//				writer.flush();

			}

			

		} catch (UnknownHostException e) {

			e.printStackTrace();

		} catch (IOException e) {

			e.printStackTrace();

		}

	}

}



TCPClientThread

public class TCPClientThread implements Runnable{



	public Socket socket = null;

	

	public BufferedReader input = null;

	

	public TCPClientThread(Socket socket){

		this.socket = socket;

		try {

			input = new BufferedReader(new InputStreamReader(this.socket.getInputStream()));

		} catch (IOException e) {

			e.printStackTrace();

		}

	}

	

	@Override

	public void run() {

		try {

			String line = null;

			while((line = input.readLine()) != null){

				System.out.println(line);

			}

		} catch (IOException e) {

			e.printStackTrace();

		}

	}

}