java - 从android服务启动的线程是否与服务一样运行？

Question

我正在从 android 服务启动一个线程，该线程使用 tcp 连接以固定的时间间隔不断上传文件到服务器。该线程有一个执行此操作的 while(true) 循环。操作会执行一段时间，但随后会停止。我尝试使用 adb logcat 进行调试，并仅在一段时间内看到我在线程内打印的某些消息。随后他们也停了下来。此外，当我停止服务时，我收到了 NullPointerException，因为在服务的 onDestroy() 方法中我使用了线程对象。

只要服务运行，线程就会被杀死并且不再运行吗？我是否需要在服务类本身的 onStart() 中执行此 while(true) 操作而不生成新线程？

提供的任何解决方案都会有很大帮助。

代码如下(部分基于this answer的kuester2000):

    public void run() 
    {           
        Log.d("TAG","Starting Thread");         
        String data = "";   
        updateServer();
        while(flag)
        {                   
            String path = extStorageDirectory + "/" + appFolder + "/" + "SAT_pingLog_" + Long.toString(System.currentTimeMillis()) + ".txt";
            createFile(path);
            int count = 0;
            while(flag && count < 32768)
            {                               
                data = "";          
                String result = Long.toString(getLatency(url));                                     
                data = Long.toString(System.currentTimeMillis()) + " " + gps[0] + " " + gps[1] + " " + strength + " " + result;
                Log.d("DEBUGGING",data);
                writeToLog(path,data);
                try 
                {
                    Thread.sleep(sleepTime);
                } 
                catch (InterruptedException e) 
                {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                count++;
            }
            updateServer();
        }           
    }public long getLatency(String Url)
    {
        long startTime = 0, endTime = 0, latency = 0;                   
        try 
        {
            HttpParams httpParameters = new BasicHttpParams();
            // Set the timeout in milliseconds until a connection is established.
            // The default value is zero, that means the timeout is not used. 
            int timeoutConnection = 10000;
            HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
            // Set the default socket timeout (SO_TIMEOUT) 
            // in milliseconds which is the timeout for waiting for data.
            int timeoutSocket = 10000;
            HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);
            DefaultHttpClient httpclient = new DefaultHttpClient(httpParameters);
            HttpHead httphead = new HttpHead(Url);
            //HttpParams httpParameters = new BasicHttpParams();                
            //HttpConnectionParams.setConnectionTimeout(httpParameters, 5000);
            //HttpConnectionParams.setSoTimeout(httpParameters, 5000);
            //HttpClient httpClient = new DefaultHttpClient(httpParameters);
            //request.setURI(new URI("http://www.google.com"));
            System.out.println("Executing request " + httphead.getURI());
            Log.d("DEBUGGING","STARTING EXECUTE");
            startTime = System.currentTimeMillis();             
            HttpResponse response = httpclient.execute(httphead);
            endTime = System.currentTimeMillis();
            Log.d("DEBUGGING","ENDING EXECUTE");
            int status = response.getStatusLine().getStatusCode();
            if (status == HttpStatus.SC_OK)                                
                latency = endTime - startTime;                                      
            else
                latency = 0;
        } 
        catch(Exception e)
        {
            Log.d("DEBUGGING","EXCEPTION CAUGHT");
            e.printStackTrace();
        }   
        Log.d("DEBUGGING","LATENCY:"+Long.toString(latency));
        return latency;
    }       
}

Answer 1

Does the thread get killed and not run as long as the service runs?

Android 组件不会注意到它们没有创建的线程。因此，虽然 IntentService 将处理它为使用 onHandleIntent() 创建的线程，但常规的 Service 将不会关注您创建的任何线程。自己 fork 。

一旦服务被销毁，它泄漏的任何线程都将继续运行，直到 Android 终止该进程。

如果您的线程意外停止，则与 Service 无关 - 同样，Service 对您 fork 的线程一无所知你自己。确保您没有通过使用空的 catch block 来默默地吃掉异常，因为我的猜测是某些东西引发了异常，导致您退出循环，但您没有记录它原因。