public class JaversTest {

      public static void main(String[] args) {
        User u1 = new User();
        User u2 = new User();

        Email e1 = new Email();
        e1.setId("id1");
        e1.setMail("Vikrant5mahajan@gmail.com");

        Email e2 = new Email();
        e2.setId("id1");
        e2.setMail("Vikrant6mahajan@gmail.com");

        u1.setEmails(Collections.singletonList(e1));
        u2.setEmails(Collections.singletonList(e2));

        Javers javers = JaversBuilder.javers().build();
        Diff diff = javers.compare(e1, e2);
        System.out.println(diff.prettyPrint());
      }

      @Data
      public static class User {
        List<Email> emails = new ArrayList<>();
      }

      @Data
      public static class Email {
        @Id
        String id;
        String mail;
      }
    }

1. ValueChange{globalId:'com.practo.test.api.diff.JaversTest$Email/id1', property:'mail', oldVal:'Vikrant5mahajan@gmail.com', newVal:'Vikrant6mahajan@gmail.com'}