You just need the descriptor for the top level message. It has the links back to all the Contained types. That is why you needed the descriptors of all of all the dependent files in order to build the file descriptor.
On Oct 10, 2:37 pm, Dale Durham <geny...@gmail.com> wrote: > Hi Benjamin, > > Thanks again, I think that am very close now. I have the hash map with > all the descriptors in it and I see that DynamicMessage has a > parseFrom method that takes (Descriptor type, Byte[] data). So I can > pass my messages byte stream in as the data, but cannot quite figure > out what to pass for the 1st parameter since each message has 3 or > more descriptors (all but one of which are dependency descriptors). I > also do not see any "merge" capability in the class. > > Can you (or anyone else) shed any light on how to do this when you get > a chance? How do you give all of the descriptors to the > DynamicMessage? > > TIA, > Dale > > On Oct 10, 10:11 am, Benjamin Wright <compuware...@gmail.com> wrote: > > > > > PS.. Just in case it want clear you should not need protoc for > > anything after you have the descriptors. The Java protobuf library > > can do all the dynamic parsing logic for you. > > > On Oct 10, 11:03 am, Benjamin Wright <compuware...@gmail.com> wrote: > > > > Dale: > > > > I'm glad to be of help. You're definitely over thinking the problem. > > > > File descriptor set- a protobuf describing one put more proto files. > > > Contains file descriptor proto (s) > > > > File descriptor proto- a protobuf describing a Single proto file > > > > File descriptor-a java class containing the descriptor information for > > > a proto file in a format usable by the dynamic message class and for > > > other "reflection" over a proto message. These can be created by > > > getting them from a compiled proto "root"class or built at run time > > > from a file descriptor proto (how you're getting them). > > > > Descriptor- a Java class that provides descriptor information for a > > > particular message type that can be serialized or parsed. You get > > > these from a file descriptor. > > > > Dynamic message is a class provided to build and parse messages for > > > which you have no compiled Java proto you must provide a descriptor > > > to parse messages but not for serialization. > > > > You should not need to parse from text unless the messages are passed > > > as proto strings which would be an awful waste of bandwidth and > > > performance. > > > > i'm not in front of a computer (on my way home from a vacation) and I > > > can't recall the exact method signatures but look at the dynamic > > > message class closer. There should be a parse our build method that > > > takes bytes or input stream, a descriptor (for a message type), and > > > optionally an extension registry. If you jabber extensions to deal > > > with let me know and I'll explain that better as It works differently > > > in Java than in cpp. > > > > :) good luck > > > Sorry about grammar in places i'm on my phone.... That was a lot to > > > type using Swype. > > > > On Oct 10, 9:22 am, Dale Durham <geny...@gmail.com> wrote: > > > > > Hi All, > > > > > Again I am new to this, so please continue to bear with me and thanks > > > > to Benjamin Wright for all the help so far!! I think that I am > > > > thinking myself into a circle between the FileDescriptors, > > > > FileDescriptorSets, FileDescriptorProtos, and so on. It is not yet > > > > really clear what is what between them all. > > > > > So, with help from Benjamin, I can get all the base proto and > > > > dependency file names and field names in one way or another. Also, I > > > > am creating the descriptors files "on the fly" if they do not already > > > > exist for each message type (I have not control over the messsages > > > > being passed and cannot add the deccriptors to the messages > > > > themselves). I am still fuzzy on if I should put all the fields into > > > > one Desriptor proto and pass that or all the files in one > > > > DescriptorSet and pass that, or something else, but I'll figure that > > > > out eventually. > > > > > Then I need to (or at least I THINK that I need to): > > > > > 1) Create a new protobuf message based on the definition defined for > > > > the protobuf files and fields based on all the Descriptor and > > > > dependency stuff above (I think this should be a DynamicMessage based > > > > on what I have seen and read) > > > > 2) Do something similar to the C++ equivalent of > > > > protobuf->ParseFromString(message.getData()); to deserialize and get > > > > the byte > > > > > array I have containing the actual message data into it > > > > > I suspect that since there is protobuf no parsing in Java, I'll have > > > > to call out to protoc again, but if so am not sure what to pass it or > > > > even if my steps above are where I really need to go next. It may be > > > > that I need to iterate through each field, get it's type, and then > > > > parse from the byte stream based on that iteration. > > > > > I also wonder if it would be faster and easier to just create a Java > > > > version of the message based on the C++ version that I am being passed > > > > in the byte array and use that instead? > > > > > The overall base steps I need to do are: > > > > 1) Get a byte array containing protobuf message that was was compiled > > > > and serialized in C++ > > > > 2) Get the structure of that message (base type and dependency files > > > > and fields in order and I can get this now, but not sure what I am > > > > doing is optimal) > > > > 3) Glue the message data into #2 above and display the it (again I > > > > think this may require a protoc call out, but maybe not) > > > > > Getting the files and fields is great and cool considering that I just > > > > started playing with these - not because I wanted to but because I > > > > have to! Now I just want to be sure am doing it the best way and need > > > > to figure out how best to glue it all together. Most of the examples I > > > > can find assume the message was compiled for Java and that I know the > > > > type (the infamous Person Class in most of them) in advance and I do > > > > not. Any additional help or thoughts are appreciated. > > > > > Thanks again, > > > > Dale -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To post to this group, send email to protobuf@googlegroups.com. 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.
