AndrewGist

ANdrewGist.java

public class UserBuilder
{
  private User;
  
  public UserBuilder()
  {
    User = new User();
    user.setFirstName("Richard");
    user.setSurname("Bradshaw");
    user.setAge(29);
    user.setEmailAddress("richard@richard.com");
  }

  public User buildGenericUser()
  {
    return User;
  }
  
  public User buildOAPUser()
  {
    user.setAge(66);
    return User;
  }
  
  public User buildTeenageUser()
  {
    user.setAge(66);
    return User;
  }
}

I would "return this;" in User class methods, so you could build the data object like this:
user
.setFirstName("Richard")
.setSurName("Bradshaw")
.setAge(29);

Looks cleaner in my point of view.