The documentation says it's immutable: http://code.google.com/apis/protocolbuffers/docs/reference/java-generated.html#messageand this code is heavily used in production, so you can bank on that.
The only way I can see that this would be accomplished would be by returning a *copy* of the underlying protocol buffer, wrapped in something without mutators. Copying protocol buffers is quite cheap and this wouldn't require volatile or any locks to work. But I don't have access to code right here, right now to check this... -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To post to this group, send email to firstname.lastname@example.org. To unsubscribe from this group, send email to protobuf+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/protobuf?hl=en.