code: public static Type of(Class<?> clazz) {
          return Optional.ofNullable( (Type) cache.computeIfAbsent( clazz, JavaBackedType::createIfAnnotated ) ).orElse( BuiltInType.UNKNOWN );
      }
docs: If clazz can be represented as a JavaBackedType, returns a JavaBackedType for representing clazz.
  If clazz can not be represented as a JavaBackedType, returns BuiltInType.UNKNOWN.
  This method performs memoization when necessary.
  @param clazz the class to be represented as JavaBackedType
  @return JavaBackedType representing clazz or BuiltInType.UNKNOWN