java - Can't find my NullPointerException -

i getting nullpointerexception can't see. know it's simple i'm overlooking. have bit reads in text file line line splits it, , uses data create custom class , pass data off added sqlite database.

public void createdata() { try {         inputstream in = this.getassets().open("stops.txt");         bufferedreader reader = new bufferedreader( new inputstreamreader(in));         string line;         line=reader.readline();         while ((line = reader.readline())!=null) {             string linevalues[] = line.split(",");             stops stop = new stops();             stop.setlon(linevalues[5]);             stop.setlat(linevalues[4]);             stop.setname(linevalues[2]);             stop.setnumber(linevalues[0]);             datasource.create(stop);         }      }catch (ioexception e) {         e.printstacktrace();     }catch(nullpointerexception n) {         n.printstacktrace();         log.d(tag,n.tostring());     }  } 

the exception occurring on datasource.create(stop); tips out there?

edit: here stack trace:

java.lang.runtimeexception: unable start activity componentinfo{ccalgary.transit.helper/ccalgary.transit.helper.mainactivity}: java.lang.nullpointerexception     @ android.app.activitythread.performlaunchactivity(activitythread.java:2306)     @ android.app.activitythread.handlelaunchactivity(activitythread.java:2356)     @ android.app.activitythread.access$600(activitythread.java:150)     @ android.app.activitythread$h.handlemessage(activitythread.java:1244)     @ android.os.handler.dispatchmessage(handler.java:99)     @ android.os.looper.loop(looper.java:137)     @ android.app.activitythread.main(activitythread.java:5195)     @ java.lang.reflect.method.invokenative(native method)     @ java.lang.reflect.method.invoke(method.java:511)     @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:795)     @ com.android.internal.os.zygoteinit.main(zygoteinit.java:562)     @ dalvik.system.nativestart.main(native method)     caused by: java.lang.nullpointerexception     @ ccalgary.transit.helper.mainactivity.createdata(mainactivity.java:341)     @ ccalgary.transit.helper.mainactivity.oncreate(mainactivity.java:71)     @ android.app.activity.performcreate(activity.java:5104)     @ android.app.instrumentation.callactivityoncreate(instrumentation.java:1080)     @ android.app.activitythread.performlaunchactivity(activitythread.java:2260) 

and here oncreate

    protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_main);     setrequestedorientation(activityinfo.screen_orientation_portrait);     settings = preferencemanager.getdefaultsharedpreferences(this);     spreferences = preferencemanager.getdefaultsharedpreferences(this);     scontext = getapplicationcontext();     boolean boot = settings.getboolean("launch", false);     if (boot == false) {         createdata();     }     datasource = new stopsdatasource(this);     dbhelper = new stopsdbhelper(this,table_stops,null,1);     mdatabase = dbhelper.getwritabledatabase();     datasource.open();     if (mdatabase.isopen()) {          log.d(tag, "database open");     } else {         log.d(tag,"database closed");     }     locationmanager = (locationmanager) getsystemservice(context.location_service);     if (locationmanager.isproviderenabled(locationmanager.gps_provider)){         //toast.maketext(this, "gps enabled in devide", toast.length_short).show();     }else{         showgpsdisabledalerttouser();     }     //mylocationlistener = new mylocationlistener();        notificationmanager = (notificationmanager)getsystemservice(notification_service); } 

data source:

public class stopsdatasource {  sqliteopenhelper dbhelper; sqlitedatabase database;  public stopsdatasource(context context) {     dbhelper = new stopsdbhelper(context, "stops", null, 1 );  }  public void open() {     database = dbhelper.getwritabledatabase(); }  public void close() {     dbhelper.close(); }  public stops create(stops stops) {     contentvalues values = new contentvalues();     values.put(stopsdbhelper.column_stop_lat, stops.getlat());     values.put(stopsdbhelper.column_stop_lon, stops.getlon());     values.put(stopsdbhelper.column_stop_name, stops.getname());     values.put(stopsdbhelper.column_stop_number,stops.getnumber());     long instertid = database.insert(stopsdbhelper.table_stops, null, values);     stops.setid(instertid);     return stops; }  } 

and db helper:

public class stopsdbhelper extends sqliteopenhelper {  public static final string table_stops = "stops"; public static final string column_id = "stopid"; public static final string column_stop_name = "name"; public static final string column_stop_lat = "lat"; public static final string column_stop_lon = "lon"; public static final string column_stop_number = "number"; public static final string table_create = "create table if not exists " + table_stops + "(" + column_id + " integer primary key autoincrement, " +  column_stop_lat + " text, " + column_stop_lon + " text, " +         column_stop_number + " text, " + column_stop_name + " text" + ")"; public stopsdbhelper(context context, string name, sqlitedatabase.cursorfactory factory, int version) {     super(context, name, factory, version); }  @override public void oncreate(sqlitedatabase sqlitedatabase) {     sqlitedatabase.execsql(table_create); }  @override public void onupgrade(sqlitedatabase sqlitedatabase, int i, int i2) {     sqlitedatabase.execsql("drop table if exists " + table_stops);     oncreate(sqlitedatabase); } } 

you calling method createdata() before initializing datasource. make before method call. ie, make initializations first before calling function may use it.

    datasource = new stopsdatasource(this);  if (boot == false) {         createdata();     }