Java Lens api I just made up

gistfile1.java

Lens<Person, Address> personAddressLens = new LensApiThatIJustMadeUp<Person, Address>(){
  @Override
  public Address get(@Nullable Person person) {
    return person.getAddress();
  }

  @Override
  public Person set(Person person, Address address) {
    return new Person(person.getFirstName(), person.getLastName(), address);
  }
};

Person person = new Person("Jack", "Smith", new Address("Default", "Default", "Default", 0));

Lens<Person, Integer> personZipCodeLens = personAddressLens.andThen(addressZipCodeLens);

personZipCodeLens.set(person, personZipCodeLens.get(person) + 1);