java - NetWork On main thread Exception

Question

Hi, I try to check network connectivity and Internet present by using following method

check = new ConnectionDetector(getApplicationContext());

conn = check.isConnectingToInternet();

public class ConnectionDetector {

private Context _context;

public ConnectionDetector(Context context){
    this._context = context;
}

/**
 * Checking for all possible internet providers
 * **/
/*public boolean isConnectingToInternet(){
    ConnectivityManager connectivity = (ConnectivityManager) _context.getSystemService(Context.CONNECTIVITY_SERVICE);
      if (connectivity != null)
      {
          NetworkInfo[] info = connectivity.getAllNetworkInfo();
          if (info != null)
              for (int i = 0; i < info.length; i++)
                  if (info[i].getState() == NetworkInfo.State.CONNECTED)
                  {
                      return true;
                  }

      }
      return false;
}*/

public boolean isConnectingToInternet(){
    try{
        ConnectivityManager cm = (ConnectivityManager)_context.getSystemService
                                                    (Context.CONNECTIVITY_SERVICE);
        NetworkInfo netInfo = cm.getActiveNetworkInfo();
        Log.d("NetInfo", String.valueOf(netInfo));
        if (netInfo != null && netInfo.isConnected())
        {
            //Network is available but check if we can get access from the network.
            URL url = new URL("http://www.Google.com/");
            HttpURLConnection urlc = (HttpURLConnection) url.openConnection();
            urlc.setRequestProperty("Connection", "close");
            urlc.setConnectTimeout(2000); // Timeout 2 seconds.
            urlc.connect();
            Log.d("NetInfo Response Code", String.valueOf(urlc.getResponseCode()));
           // Toast.makeText(getApplicationContext(), String.valueOf(urlc.getResponseCode()), Toast.LENGTH_LONG).show();
            if (urlc.getResponseCode() == 200)  //Successful response.
            {
                return true;
            } 
            else 
            {
                 Log.d("NO INTERNET", "NO INTERNET");
                return false;
            }
        }
    }
    catch(Exception e)
    {
        e.printStackTrace();
    }
    return false;
}

}

Note :

But this will return NetworkOnMainThread Exception like follows.kindly any one suggest me what mistakes i made.......

03-27 12:53:35.617: W/System.err(1095): android.os.NetworkOnMainThreadException
03-27 12:53:35.627: W/System.err(1095):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1084)
03-27 12:53:35.637: W/System.err(1095):     at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
03-27 12:53:35.637: W/System.err(1095):     at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
03-27 12:53:35.647: W/System.err(1095):     at java.net.InetAddress.getAllByName(InetAddress.java:220)
03-27 12:53:35.647: W/System.err(1095):     at libcore.net.http.HttpConnection.<init>(HttpConnection.java:71)
03-27 12:53:35.657: W/System.err(1095):     at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
03-27 12:53:35.668: W/System.err(1095):     at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:351)
03-27 12:53:35.668: W/System.err(1095):     at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:86)
03-27 12:53:35.677: W/System.err(1095):     at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
03-27 12:53:35.687: W/System.err(1095):     at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:308)
03-27 12:53:35.699: W/System.err(1095):     at libcore.net.http.HttpEngine.connect(HttpEngine.java:303)
03-27 12:53:35.699: W/System.err(1095):     at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:282)
03-27 12:53:35.707: W/System.err(1095):     at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:232)
03-27 12:53:35.718: W/System.err(1095):     at libcore.net.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:80)
03-27 12:53:35.727: W/System.err(1095):     at com.slet.routemytrips.beta.ConnectionDetector.isConnectingToInternet(ConnectionDetector.java:50)
03-27 12:53:35.727: W/System.err(1095):     at com.slet.routemytrips.beta.Disclaimer$1.onClick(Disclaimer.java:178)
03-27 12:53:35.738: W/System.err(1095):     at android.view.View.performClick(View.java:3480)
03-27 12:53:35.738: W/System.err(1095):     at android.view.View$PerformClick.run(View.java:13983)
03-27 12:53:35.748: W/System.err(1095):     at android.os.Handler.handleCallback(Handler.java:605)
03-27 12:53:35.757: W/System.err(1095):     at android.os.Handler.dispatchMessage(Handler.java:92)
03-27 12:53:35.757: W/System.err(1095):     at android.os.Looper.loop(Looper.java:137)
03-27 12:53:35.767: W/System.err(1095):     at android.app.ActivityThread.main(ActivityThread.java:4340)
03-27 12:53:35.777: W/System.err(1095):     at java.lang.reflect.Method.invokeNative(Native Method)
03-27 12:53:35.777: W/System.err(1095):     at java.lang.reflect.Method.invoke(Method.java:511)
03-27 12:53:35.787: W/System.err(1095):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
03-27 12:53:35.797: W/System.err(1095):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
03-27 12:53:35.807: W/System.err(1095):     at dalvik.system.NativeStart.main(Native Method)
03-27 12:57:05.237: D/dalvikvm(90): GC_CONCURRENT freed 666K, 10% free 12624K/14023K, paused 6ms+10ms

Answer 1

You can't make HTTP requests on the main thread, it would cause the UI to freeze up. So it throws that exception. You need to do it in an AsyncTask or another Thread.