Immutables

import org.immutables.value.Value;
// Define abstract value type
@Value.Immutable
public interface ValueObject {
  String name();
  List<Integer> counts();
  Optional<String> description();
}

// Use generated immutable implementation
ValueObject valueObject =
    ImmutableValueObject.builder()
        .name("My value")
        .addCounts(1)
        .addCounts(2)
        .build();

// Or you can configure different @Value.Style
@Value.Immutable
abstract class AbstractItem {
  abstract String getName();
  abstract Set<String> getTags();
  abstract Optional<String> getDescription();
}

// Use generated value object
Item namelessItem = Item.builder()
    .setName("Nameless")
    .addTags("important", "relevant")
    .setDescription("Description provided")
    .build();

Item namedValue = namelessItem.withName("Named");