code: protected void registerDefaultDatatypes() {
  
      registerStandardDatatype(String.class);
      registerStandardDatatype(Boolean.class);
      registerStandardDatatype(Character.class);
      registerStandardDatatype(Currency.class);
      registerCustomDatatype(Datatype.class); // internal trick...
      registerNumberDatatypes();
      registerJavaTimeDatatypes();
      registerJavaUtilDateCalendarDatatypes();
    }
docs: Registers the default datatypes.