private int wordBack(int offset){
  int x=wordBI.preceding(offset);
  if (x < offset - 15) {
    x=offset;
  }
  if (x < 0) {
    x=0;
  }
  return x;
}

private int wordBack ( int offset ) { int x = wordBI . preceding ( offset ) ; if ( x < offset - 15 ) { x = offset ; } if ( x < 0 ) { x = 0 ; } return x ; }
find last word boundary before offset .
