Assuming you know the Java Enum Type for which the EnumValueDescriptor
is describing a type of...


will return the appropriate java enum value.

On May 23, 1:42 pm, Jim Mayer <> wrote:
> In the Java protocol buffer binding, is there a way to get the Java
> enum value using protocol buffer reflection?  Specifically, I'd like
> to be able to write something like the following:
>   Object getFieldValue(MessageOrBuilder source, FieldDescriptor field)
> {
>     Object value = source.getField(field);
>     if (value instanceof EnumValueDescriptor) {
>        return <the Java enum corresponding to the descriptor>;
>     } else {
>       return value;
>     }
>   }
> As far as I can tell, this isn't possible as the methods that return
> enums from the descriptors are all static on the enum class.  Since
> they are static, there is no way (short of reflection games) to invoke
> them unless one has the class in hand.  I would enjoy being proved
> wrong :-)
> What we'd really like to see is an easy mechanism that would give us
> the following:
>    Something explicitValue = message.getXXX();
>    Object reflectionValue =
> message.getTheJavaValueFromAFieldDescriptor(<the field descriptor for
> XXX>);
>    assert explictValue == reflectionValue;
> Similarly, we'd like to be able do the same thing for 'setXXX' methods
> for builders, however in this case it's easy to go from an enum value
> to its descriptor so we can get by with the 'setField' method.
> Thanks!
> -- Jim

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