TCP客户端/服务器程序，DataInputStream / DataOutputStream问题

2 回答

• 8

  您正在使用 writeBytes 在客户端中编写字符串，并使用 readUTF 来读取服务器中的相同字符串 .

  如果您查看这两种方法的javadoc，您将看到您正在以一种格式书写，然后在另一种格式中阅读 . 具体来说， readUTF 期望输入以2字节字符计数开始，然后是字符的"modified UTF-8"编码 . 但 writeBytes 只是每个字符写入1个字节 . 通常， readUTF 将尝试读取比 writeBytes 写入更多的字节...并且套接字流将冻结 .

  您应该使用 writeUTF 而不是 writeBytes ...

  回复于 2024-04-29T01:21:25+08:00
• 3

  斯蒂芬C是对的 . 我做了一些小修改，但原因是'在另一边使用write *时使用read *' .

  这是运行代码：
  客户：

  import java.io.DataInputStream;
  import java.io.DataOutputStream;
  import java.io.IOException;
  import java.net.Socket;
  import java.net.UnknownHostException;
  
  public class TCPClient {
  
      public TCPClient() {
      }
  
      public static void main(String args[]) throws UnknownHostException, IOException {
          Socket socket = new Socket("localhost", 9701);
          DataInputStream input = new DataInputStream(socket.getInputStream());
          DataOutputStream output = new DataOutputStream(socket.getOutputStream());
  
          boolean stop = false;
          while (!stop) {
              System.out.println("client->server: hello...");
              output.writeUTF("hello");
  
              System.out.println("client: waiting...");
              String response = input.readUTF();
              System.out.printf("client: got response: %s\n", response);
          }
          socket.close();
      }
  }
  

  服务器：

  import java.io.DataInputStream;
  import java.io.DataOutputStream;
  import java.io.IOException;
  import java.net.ServerSocket;
  import java.net.Socket;
  
  public class TCPServer extends Thread {
  
      final static int TCP_SERVER_PORT = 9701;
      private Socket socket;
  
      public TCPServer(Socket sock) {
          socket = sock;
      }
  
      public void run() {
          System.out.println(this.socket.getPort() + " working or sleeping for 5 seconds");
  
          try {
              Thread.sleep(1000);
          } catch (InterruptedException e) {
              e.printStackTrace();
          }
  
          DataInputStream clientinp;
          DataOutputStream clientout;
  
          try {
              clientinp = new DataInputStream(socket.getInputStream());
              clientout = new DataOutputStream(socket.getOutputStream());
  
              while (true) {
                  System.out.println("reading...");
                  String sentence = clientinp.readUTF();
                  System.out.printf("read: %s", sentence);
                  clientout.writeUTF(String.format("answer: %s", sentence));
              }
          } catch (IOException e) {
              e.printStackTrace();
          } finally {
              try {
                  socket.close();
              } catch (IOException e) {
                  e.printStackTrace();
              }
          }
      }
  
      public static void main(String args[]) throws IOException {
          ServerSocket serversocket;
          serversocket = new ServerSocket(TCP_SERVER_PORT);
          while (true) {
              Socket clientsocket = serversocket.accept();
              new TCPServer(clientsocket).start();
          }
      }
  }
  

  回复于 2024-04-29T01:21:25+08:00