java异常

Question

我有两个java类在不同的线程上运行。一个类(class)连接到互联网，而另一个类(class)则连接到互联网类监视连接状态。我想抛出 IOException 以防类建立连接延迟在读取服务器响应时，同时如果从服务器读取了一些响应，我不想抛出异常。

我想出了这段代码。

我的问题是我想在 NetworkMonitor 类中抛出 IOException ，该异常将被捕获NetworkConnector 类是主类。然而编译器提示未捕获的异常。

  public class NetworkConnector{
  //method that connects to the server to send or read data.
  public String sendData(String url ,String data){
     try{

        //start the monitor before we read the serverResponse
        new NetworkMonitor().startMonitor();

        int read ;
        while ((read = inputStream.read()) != -1) {
           //read data.
           sb.append((char) read);

           //monitor if we are reading from Server if not reading count 10 to 0 and throw IoException. 
           new NetworkMonitor().resetCounter();
        }

     } catch(IOException ex){
        //all IOException should be caught here.
     }

  }

}

//监视是否发生网络 Activity 的类。

  public class NetworkMonitor implements Runnable {

  private final int WAITTIME =10;
  private int counter = WAITTIME;


  public void run(){
     try{

        while(counter > 0){
           //waiting here
           counter--; //decrement counter. 
           Thread.sleep(1000);     
        }

        //when counter is at zero throw iOexception 
        throw new IOException("Failed to get server Response");

     } catch(InterruptedException e){
        System.out.println(e.getMessage());
     } catch(IOException e){
        //i want to throw the IOEception here since the exception should 
        //be caught by the networkConnector class not the monitor class but the compiler complains.
        // unreported exception java.io.IOException; must be caught or declared to be thrown
        throw new IOException(e.getMessage());

        //throwing another exception type is okay ===>why cant we throw the same type of exception we caught.
         throw new IllegalArgumentException(e.getMessage()); 
     }


  }

  //reset the counter if called.
  public void resetCounter(){
     counter = WAITTIME;
  }

  public void startMonitor(){
     Thread t = new Thread(this);
     t.start();
  }

}

Answer 1

您有一个更基本的问题

• 一个线程中抛出的异常需要传递给另一个线程。您可以使用 ExecutorService 和 Future 来执行此操作。
• 要实现超时，您可以使用 ScheduledExecutorService。这将允许您安排延迟且可取消的任务。
• 一个线程中抛出的异常不会解除阻塞读取。您需要关闭连接才能解除阻止，这将导致 IOException。
• 一旦准备好这些，您就可以使用 Callable 而不是 Runnable 来引发已检查的异常。

而不是睡1秒，睡10次。你可以睡 10 秒钟。