protobuf syntax = "proto2"; option optimize_for = LITE_RUNTIME; message MyMessage { } bash protoc --javanano_out=output_directory my.proto MyMessage myMessage = MyMessage.newBuilder().build(); byte[] compressedData = myMessage.toByteString().toByteArray(); protobuf syntax = "proto2"; message MyMessage { required int32 id = 1; optional string name = 2; repeated string tags = 3; }