public Collection<AISValidationFailure> failures(){
  return Collections.unmodifiableCollection(failureList);
}

public Collection < AISValidationFailure > failures ( ) { return Collections . unmodifiableCollection ( failureList ) ; }
gets all failures , if there were any . the collection will be unmodifiable and immutable ; if it is not empty , subsequent invocations of this method may all return same collection instance , but only as long as no additional failures are reported . if new failures are reported , they and the previous will be in a new collection instance .
