My problem is to serialize protobuf data in C++ and deserialize the data in Java probably. Here is the code I use to the hints given by dcn: With this I create the protobuf data in C++ and write it to an ostream which is send via socket. Name name; name.set_name("platzhirsch"); boost::asio::streambuf b; std::ostream os(&b); ZeroCopyOutputStream *raw_output = new OstreamOutputStream(&os); CodedOutputStream *coded_output = new CodedOutputStream(raw_output); coded_output->WriteLittleEndian32(name.ByteSize()); name.SerializeToCodedStream(coded_output); socket.send(b); This is the Java side where I try to parse it: NameProtos.Name name = NameProtos.Name.parseDelimitedFrom(socket.getInputStream()); System.out.println(name.newBuilder().build().toString()); However by this I get this Exception: **com.google.protobuf.UninitializedMessageException: Message missing required fields: name** What am I missing? --- The flawed code line is: `name.newBuilder().build().toString()` This would have never worked, a new instance is created with uninitialized name field. Anyway the answer here solved the rest of my problem. One last thing, which I was told in the protobuf mailinglist: In order to flush the CodedOutputStreams, the objects have to be deleted! delete coded_output; delete raw_output;
what does your code look like which fills the received array?