question: returns an immutable set of all nine primitive types including void . note that a simpler way to test whether a class instanceis a member of this set is to call class #isprimitive . concode_field_sep Map<Class<?>,Class<?>> PRIMITIVE_TO_WRAPPER_TYPE concode_elem_sep Map<Class<?>,Class<?>> WRAPPER_TO_PRIMITIVE_TYPE concode_field_sep void add concode_elem_sep Set<Class<?>> allWrapperTypes concode_elem_sep boolean isWrapperType concode_elem_sep Class<T> wrap concode_elem_sep Class<T> unwrap
target: Set < Class < ? >> function ( ) { return PRIMITIVE_TO_WRAPPER_TYPE . keySet ( ) ; }