android - Unable to start activity ComponentInfo{example.}: java.lang.NullPointerException: println needs a message -

java.lang.nullpointerexception: println needs message  

my code:

public class viewmupuh extends activity implements onclicklistener {     private static string position = null;      private textview textjudul, textlirik;     private button bupdate;      @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.detail_mupuh);         intent intent = getintent();         position = intent.getstringextra("position");         log.d("value of position",position);         dbhelper db = new dbhelper(this);         lirik lirik = db.getlirik(position);         textjudul = (textview) findviewbyid(r.id.judul_details);         textjudul.settext(lirik.getjudul());         textlirik = (textview) findviewbyid(r.id.lirikdetails);         textlirik.settext(lirik.getlirik());          bupdate = (button) findviewbyid(r.id.bupdatedetails);         bupdate.setonclicklistener(this);     }      @override     public void onclick(view v) {         intent intent = new intent(getapplicationcontext(), editlirik.class);         intent.putextra("position value", position);         startactivity(intent);     } } 

thanks

this happens because position = intent.getstringextra("position"); returns null , log.d("value of position",position); raises exception.

try changing

log.d("value of position",position); 

for

log.d("value of position", "" + position); // if position null log "null" 

or

if (position != null) {     log.d("value of position", position); } 

anyway, take account position can null after intent.getstringextra("position"); in rest of code.