code: public PenalizingValidation getPenalizingValidation(Object key){
          return penalties == null ? null : penalties.get(key);
      }
docs: Retrieve the penalizing validation object corresponding to the given key.
  If no penalty has been added with this key, <code>null</code> is returned.
  
  @param key key specified when adding the penalizing validation
  @return retrieved validation object, or <code>null</code> if no validation
  object was added with this key