Does protobuf (protocol buffers) allow custom types?

Question

I want to use protobuf in Java and Flash. All of them has protobuf implementation. I want to create the following structure:

class UserDetails
{
  int age;
  int weight;
  int lenght;
}

class User
{
  string firstName;
  string lastName;
  UserDetails details;
}

The question about UserDetails details; Is it allowed in Google protocol buffer?

Answer 1

Yes, you can even define nested messages:

message User {
    required string firstName = 1;
    required string secondName = 2;

    message UserDetails {
        required int age = 1;
        required int weight = 2;
        required int lenght = 3;
    }

    required UserDetails details = 3;
}

You can get much more information about messages here.