TwigConvertersSample.java

TwigConvertersSample.java

  public enum MyEnum {
    TEST, ABC
  }

  public static class Bar {
    @Id
    Integer myKey;

    Map<MyEnum, Integer> map = new HashMap<MyEnum, Integer>();
  }

  public static class MyEnumToString implements SpecificConverter<MyEnum, String> {

    @Override
    public String convert(MyEnum source) {
      return source.toString();
    }
  }

  public static class StringToMyEnum implements SpecificConverter<String, MyEnum> {

    @Override
    public MyEnum convert(String source) {
      return MyEnum.valueOf(source);
    }
  }


  @Test
  public void usingEnumAsKey() {
    ObjectDatastore datastore = createDatastore();
    Bar bar = new Bar();
    bar.map.put(MyEnum.ABC, 10);
    Key key = datastore.store().instance(bar).now();

    datastore = createDatastore();

    Bar b2 = datastore.load(key);
    System.out.println(b2.map);
  }

  private ObjectDatastore createDatastore() {
    ObjectDatastore datastore = new AnnotationObjectDatastore() {
      @Override
      protected CombinedConverter createTypeConverter() {
        CombinedConverter converter = new CombinedConverter();
        converter.append(new PrimitiveConverter());
        converter.append(new CollectionConverter(converter));
        converter.append(new MyEnumToString());
        converter.append(new StringToMyEnum());


        EngineConverters.registerAll(converter);
        CoreConverters.registerAll(converter);
        MapConverters.registerAll(converter);
        return converter;
      }
    };

    return datastore;
  }