Question

我在while循环中有开关盒。而在一种情况下，其中有一个同步阻止，其后是break语句。该break语句导致循环中断而不是大小写中断。下面是代码。

while (!shutdown && !Thread.currentThread().isInterrupted()) {
            try {
                logger.info("Trying to Read message");
                ServerResponseMessage response = gson.fromJson(jsonReader, ServerResponseMessage.class);
                logger.info("Message Reading completed.");
                if(response == null) {
                    logger.info("Received EOS Response, closing thread.");
                    break;
                }
                switch (response.getRequestType()) {
                /* GET request type is considered as the request for the new object */
                case GET:
                    object = response.getObject();
                    synchronized (requestLock) {
                        requestLock.notifyAll();
                    }
                    break;
                    /*
                     * If client receives HEARTBEAT message from Server, client need to response as
                     * Ack.
                     */
                case HEARTBEAT:
                    logger.info("Received Hearbeat");
                    ServerResponseMessage message = new ServerResponseMessage(RequestType.HEARTBEAT_ACK, null);
                    JsonWriter jsonWriter = new JsonWriter(new OutputStreamWriter(serverSocket.getOutputStream()));
                    jsonWriter.jsonValue(new Gson().toJson(message));
                    jsonWriter.flush();
                    logger.info("Sent Hearbeat Ack");
                    break;
                default:
                    break;
                }
                logger.info("Completed reading.");
            } catch (IOException e) {
                logger.warn("Error while reading client", e);
                shutdown = true;
            }
        }

在上面的代码中，GET情况导致循环中断，根据日志，它在notifyAll方法之后直接跳出while循环。请帮助。谢谢。

Answer 1

为您的Switch考虑一个标签，以便您可以在需要时轻松破坏该标签。

LOOP1:
while (condition) {
   MY_LABEL:
   switch (variable) {
      case (a):
        break LOOP1; // will break the loop -> Also continue; works as well.
        break MY_LABEL; // it will break the switch and continue on loop
   }
}

这通常对于嵌套循环很有用。有关更多信息，请参见the docs。

While循环中的Java Switch情况，带有导致循环中断的同步块

1 个答案: