public static <V>boolean addDistinctEntry(List<V> sourceList,V entry){
  return (sourceList != null && !sourceList.contains(entry)) ? sourceList.add(entry) : false;
}

public static < V > boolean addDistinctEntry ( List < V > sourceList , V entry ) { return ( sourceList != null && ! sourceList . contains ( entry ) ) ? sourceList . add ( entry ) : false ; }
add distinct entry to list
