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
   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.


-- Jim

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