public int compareSourceLines(BugCollection lhsCollection,BugCollection rhsCollection,SourceLineAnnotation lhs,SourceLineAnnotation rhs){
  if (lhs == null || rhs == null) {
    return compareNullElements(lhs,rhs);
  }
  int cmp=compareClassesByName(lhsCollection,rhsCollection,lhs.getClassName(),rhs.getClassName());
  if (cmp != 0) {
    return cmp;
  }
  return 0;
}

public int compareSourceLines ( BugCollection lhsCollection , BugCollection rhsCollection , SourceLineAnnotation lhs , SourceLineAnnotation rhs ) { if ( lhs == null || rhs == null ) { return compareNullElements ( lhs , rhs ) ; } int cmp = compareClassesByName ( lhsCollection , rhsCollection , lhs . getClassName ( ) , rhs . getClassName ( ) ) ; if ( cmp != 0 ) { return cmp ; } return 0 ; }
compare source line annotations .
