客戶端向服務(wù)發(fā)送數(shù)據(jù)。服務(wù)器收到數(shù)據(jù)后給客戶端反饋。可是程序運(yùn)行之后并沒(méi)有返回?cái)?shù)據(jù)給客戶端，而且程序也沒(méi)有停下來(lái)。class TcoClient{    public static void main(String[] args) throws IOException {       BufferedInputStream bis = new BufferedInputStream(new FileInputStream("C:\\Users\\Administrator\\Desktop\\abs.apk"));       Socket socket = new Socket(InetAddress.getLocalHost(), 10000);       OutputStream os = socket.getOutputStream();       byte[] buf = new byte[1024];       int len;       while ((len = bis.read(buf)) != -1) {           os.write(buf, 0, len);       }       InputStream is = socket.getInputStream();       int backLen = is.read(buf);       System.out.println(new String(buf, 0, backLen));       os.close();   }}class TcpServer {   public static void main(String[] args) throws IOException {       ServerSocket serverSocket = new ServerSocket(10000);       Socket socket = serverSocket.accept();       InputStream is = socket.getInputStream();       BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("C:\\Users\\Administrator\\Desktop\\cde.apk"));       byte[] buf = new byte[1024*1024];       int len;       while ((len = is.read(buf)) != -1) {           bos.write(buf, 0, len);       }       OutputStream os = socket.getOutputStream();       os.write("文件傳輸完成".getBytes());   }