title: Protobuf 3.0 Any Type pack/unpack
body: <p>I would like to know how to transform a Protobuf <strong>Any</strong> Type to the original Protobuf message type and vice versa. In Java from Message to Any is easy:</p>
  
  <pre><code>Any.Builder anyBuilder = Any.newBuilder().mergeFrom(protoMess.build());
  </code></pre>
  
  <p>But how can I parse that <strong>Any</strong> back to the originial message (e.g. to the type of "protoMess")? I could probably parse everything on a stream just to read it back in, but that's not what I want. I want to have some transformation like this:</p>
  
  <pre><code>ProtoMess.MessData.Builder protoMessBuilder = (ProtoMess.MessData.Builder) transformToMessageBuilder(anyBuilder)
  </code></pre>
  
  <p>How can I achieve that? Is it already implemented for Java? The <a href="https://developers.google.com/protocol-buffers/docs/proto3#any" title="Language Guide">Protobuf Language Guide</a> says there were pack and unpack methods, but there are none in Java. 
  Thank you in Advance :)</p>