protobuf syntax = "proto2"; message Person { required string name = 1; optional int32 age = 2; repeated string hobbies = 3; } protoc --java_out=<output_directory> <proto_file> Person person = Person.newBuilder() .setName("Alice") .setAge(25) .addHobbies("reading") .addHobbies("hiking") .build(); // Serialize byte[] serializedPerson = person.toByteArray(); // Deserialize Person deserializedPerson = Person.parseFrom(serializedPerson); System.out.println(deserializedPerson);