public ProblemList<?> getQualityProblems() {
   ProblemList<Model> pl = null;
   try {
     if (this._problemList != null && this._problemList.size() > 0) {
       pl = new ProblemList<Model>(this._problemList);
     } else {
       pl = new ProblemList<Model>();
     }
   } catch (ProblemListInitialisationException e) {
     logger.error(e.getMessage());
   }
   return pl;
 }
 /**
  * Returns list of problematic Quads
  *
  * @return list of problematic quads
  */
 public ProblemList<?> getQualityProblems() {
   ProblemList<Model> tmpProblemList = null;
   try {
     if (this.problemList != null && this.problemList.size() > 0) {
       tmpProblemList = new ProblemList<Model>(this.problemList);
     } else {
       tmpProblemList = new ProblemList<Model>();
     }
   } catch (ProblemListInitialisationException problemListInitialisationException) {
     logger.error(problemListInitialisationException.getMessage());
   }
   return tmpProblemList;
 }