The JVMS drafts for value classes and primitive classes define the following new class modifiers:
  - ACC_VALUE
  - ACC_PERMITS_VALUE
  - ACC_PRIMITIVE

Those new flags are defined in "Table 4.1-B. Class access and property modifiers".

Those new modifiers should be supported by the java.lang.reflect.Modifier class, which would prevent code duplication like in java.lang.Class where the missing flags are defined locally as private constant fields.