code: private boolean isWrapper( Class<?> cls ) {
          if ( null == cls )
              return false;
          if ( Boolean.class.isAssignableFrom(cls) ) switch ( kind ) {
              case EQ: case NE: case BOOL_OR: case BOOL_ORX: case BOOL_AND:
              case BOOL_ANDX: case BIT_AND: case BIT_ANDX: case BIT_OR:
              case BIT_ORX: case XOR: case XORX:
                  return true;
              default:
                  return false;
          }
          if (Character.class.isAssignableFrom(cls)
              || Number.class.isAssignableFrom(cls)) switch ( kind ) {
              case BOOL_AND: case BOOL_ANDX: case BOOL_OR: case BOOL_ORX:
                  return false;
              default:
                  return true;
          }
          return false;
      }
docs: Is the class a wrapper type.
  Also apply valid operator type to response.
  @param cls the type to inspect
  @return is a wrapper type with valid operators