android HttpRequest每3秒通过一次服务

Question

我只想获取数据并在吐司消息或通知消息上显示。所以我在主线程中创建了一个服务。（UI线程）我刚刚启动了一个新的线程来获取数据并将其放在Logs in Service中。代码：

public class HelloService extends Service 
{

@Override
public IBinder onBind(Intent intent)
{
    // TODO Auto-generated method stub
    return null;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId)
{
    MyThread th = new MyThread();
    th.start();
    try 
    {
        th.join();
    } 
catch (InterruptedException e) 
    {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    return START_STICKY;  
}



}

class MyThread extends Thread
{
    public void run()
    {
        while(true)
        {
            try
            {
                Thread.sleep(3000);
            }
            catch (InterruptedException e1)
            {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
        String response;
        String dataToSend = "http://berkrevolution.com";
        Log.i("FROM STATS SERVICE DoBackgroundTask", dataToSend);
        HttpClient httpClient = new DefaultHttpClient();
        HttpPost httpPost = new HttpPost(dataToSend);

        try 
        {
            httpPost.setEntity(new StringEntity(dataToSend, "UTF-8"));

            // Set up the header types needed to properly transfer JSON
            httpPost.setHeader("Content-Type", "application/x-www-form-urlencoded");
            httpPost.setHeader("Accept-Encoding", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
            httpPost.setHeader("Accept-Language", "en-US");

            // Execute POST
            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity responseEntity = httpResponse.getEntity();
            if (responseEntity != null) 
            {
                response = EntityUtils.toString(responseEntity);
                Log.i("sonuc", response);
            } 
            else 
            {
                response = "{\"NO DATA:\"NO DATA\"}";
            }
        } 
        catch (ClientProtocolException e)
        {
            response = "{\"ERROR\":" + e.getMessage().toString() + "}";
        } catch (IOException e) {
            response = "{\"ERROR\":" + e.getMessage().toString() + "}";
        }
        }
    }
}

但是20秒后我收到了一个错误。错误是：

11-22 13:30:44.831: A/libc(29854): Fatal signal 6 (SIGABRT) at 0x00000470 (code=0), thread 29854 (le.project1)

即使主程序关闭，我也需要提供全天候工作的服务。但是，我试图使用服务，我得到了这个错误。我该如何解决这个问题？

我如何在UI线程中启动服务：

 public void startServ(View view) 
    {
        //Toast.makeText(this, "Hey", Toast.LENGTH_LONG).show();
        Intent intent = new Intent(MainActivity.this, HelloService.class);
        startService(intent);

    }