Question

我正在使用java套接字进行通信。在客户端我有一些处理，此时我发送一个对象给客户。代码如下：

while (true) {
  try {
    Socket server = new Socket("localhost", 3000);
    OutputStream os = server.getOutputStream();
    InputStream is = server.getInputStream();

    CommMessage commMessage = new CommMessageImpl();
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    ObjectOutputStream oos = new ObjectOutputStream(bos);
    oos.writeObject(commMessage);
    os.write(bos.toByteArray());
    os.flush();

    byte[] buff = new byte[512];
    int bytesRead = 0;
    ByteArrayOutputStream receivedObject = new ByteArrayOutputStream();
    while ((bytesRead = is.read(buff)) > -1) {
      receivedObject.write(buff, 0, bytesRead);
      System.out.println(receivedObject);
    }
    os.close();
    Thread.sleep(10000);
  } catch (IOException e) {
  } catch (InterruptedException e) {
  }
}

接下来在服务器端我有以下代码来读取对象并写入响应（这只是一个回显消息）

public void startServer() {
  Socket client = null;
  try {
    server = new ServerSocket(3000);
    logger.log(Level.INFO, "Waiting for connections.");
    client = server.accept();
    logger.log(Level.INFO, "Accepted a connection from: " + client.getInetAddress());
    os = new ObjectOutputStream(client.getOutputStream());
    is = new ObjectInputStream(client.getInputStream());

    // Read contents of the stream and store it into a byte array.
    byte[] buff = new byte[512];
    int bytesRead = 0;
    ByteArrayOutputStream receivedObject = new ByteArrayOutputStream();
    while ((bytesRead = is.read(buff)) > -1) {
      receivedObject.write(buff, 0, bytesRead);
    }

    // Check if received stream is CommMessage or not contents.
    CommMessage commMessage = getCommMessage(receivedObject);
    if (commMessage != null) {
      commMessage.setSessionState(this.sessionManager.getState().getState());
      ByteArrayOutputStream bos = new ByteArrayOutputStream();
      ObjectOutputStream oos = new ObjectOutputStream(bos);
      oos.writeObject(commMessage);
      os.write(bos.toByteArray());
      System.out.println(commMessage.getCommMessageType());
    } else {
      processData(receivedObject, this.sessionManager);
    }
    os.flush();
    } catch (IOException e) {
    } finally {
      try {
        is.close();
        os.close();
        client.close();
        server.close();
      } catch (IOException e) {
    }
  }
}

如果我不尝试在客户端读取数据（如果我排除与读取相关的代码），则上述代码可以正常工作。但是，如果我有这个代码，由于某种原因，我在访问输入流时会遇到某种死锁。我可能做错了什么想法？提前谢谢。

Answer 1

客户端和服务器都试图读取整个输入流（即一切都达到EOF），但都没有发送EOF（通过调用套接字上的shutdownOutput()。）

为什么需要暂时将对象数据存储在ByteArrayOutputStream中？如果直接从套接字输入流中读取，这可能更容易修复。

Java死锁问题

1 个答案: