code: public <Concept, S extends Statement> void put(final Class<Concept> conceptClass,
                                                     final AbstractStatementConverter<Concept, S> converter) {
  
          // Check sanity
          if (conceptClass == null) {
              throw new NullPointerException("Cannot handle null 'conceptClass' argument.");
          }
          if (converter == null) {
              throw new NullPointerException("Cannot handle null 'converter' argument.");
          }
      }
docs: Adds the supplied {@link AbstractStatementConverter} for the given Concept class.
  Null arguments are not permitted.
  
  @param converter    The Converter to add.
  @param conceptClass The class to convert into a Statement.
  @param <Concept>    The type to convert.
  @param <S>          The Statement subclass.