twitter - Tweet from an android service -

i'd tweet android service class. have implemented tweeting android activity class , working fine. however, service class i'm not able same. here snippet used. have used twitter4j library. status string.

                    configurationbuilder builder = new configurationbuilder();                     builder.setoauthconsumerkey(constants.consumer_key);                     builder.setoauthconsumersecret(constants.consumer_secret);                      sharedpreferences msharedpreferences;                      msharedpreferences = getapplicationcontext()                             .getsharedpreferences("mypref", 0);                      final string pref_key_oauth_token = "oauth_token";                     final string pref_key_oauth_secret = "oauth_token_secret";                      // access token                     string access_token = msharedpreferences.getstring(                             pref_key_oauth_token, "");                     // access token secret                     string access_token_secret = msharedpreferences.getstring(                             pref_key_oauth_secret, "");                      accesstoken accesstoken = new accesstoken(access_token,                             access_token_secret);                     twitter twitter = new twitterfactory(builder.build())                             .getinstance(accesstoken);                      // update status                     twitter4j.status response = twitter.updatestatus(status);