protobuf syntax = "proto3"; package com.example; message Person { string name = 1; int32 age = 2; repeated string email = 3; } protoc --java_out=src/main/java/ proto/person.proto PersonOuterClass.Person person = PersonOuterClass.Person.newBuilder() .setName("John Doe") .setAge(30) .addEmail("john.doe@example.com") .addEmail("johndoe@gmail.com") .build(); byte[] serializedData = person.toByteArray(); PersonOuterClass.Person parsedPerson = PersonOuterClass.Person.parseFrom(serializedData);