java - how to use try catch instead force close? -

i have code in android , java. want show dialog user when internet connection has problems or website inaccessible. try put code try-catch block yet when internet connection has problem app closed. want show message user, not close app.

 httppost ht = new httppost("http://yahoo.com");         httpclient hc = new defaulthttpclient();         httpresponse hr = null;          try {             hr = hc.execute(ht);          } catch (clientprotocolexception e) {             // todo auto-generated catch block             e.printstacktrace();         } catch (ioexception e) {             // todo auto-generated catch block             e.printstacktrace();         }           string htmltemp = "";         try {              httpentity = hr.getentity();              htmltemp = new string(entityutils.tostring(he));          } catch (ioexception e) {             // todo auto-generated catch block             e.printstacktrace();         } 

you can try add unknownhostexception catch, or can use method before calling request :

  public static boolean hasconnection() {     connectivitymanager cm = (connectivitymanager) mbridgeapp.getcontext().getsystemservice(         context.connectivity_service);      networkinfo wifinetwork = cm.getnetworkinfo(connectivitymanager.type_wifi);     if (wifinetwork != null && wifinetwork.isconnected()) {       return true;     }      networkinfo mobilenetwork = cm.getnetworkinfo(connectivitymanager.type_mobile);     if (mobilenetwork != null && mobilenetwork.isconnected()) {       return true;     }      networkinfo activenetwork = cm.getactivenetworkinfo();     if (activenetwork != null && activenetwork.isconnected()) {       return true;     }      return false;   }