code: public static boolean isPrimitiveType(ClassNode cn) {
          return  cn == boolean_TYPE ||
                  cn == char_TYPE ||
                  cn == byte_TYPE ||
                  cn == short_TYPE ||
                  cn == int_TYPE ||
                  cn == long_TYPE ||
                  cn == float_TYPE ||
                  cn == double_TYPE ||
                  cn == VOID_TYPE;
      }
docs: Test to determine if a ClassNode is a primitive type.
  Note: this only works for ClassNodes created using a
  predefined ClassNode
  
  @see #make(Class)
  @see #make(String)
  @param cn the ClassNode containing a possible primitive type
  @return true if the ClassNode is a primitive type