GSON. workaround for enum and int

From kjones' answer, here's a Kotlin translation:

  enum class ObjectTypeEnum(val value:Int) {
    @SerializedName("0")
    UNKNOWN_TYPE(0),
    @SerializedName("11")
    SIMPLE_TYPE(11),
    @SerializedName("42")
    COMPLEX_TYPE(42)
  }

Or, without needing the Int values:

  enum class ObjectTypeEnum {
    @SerializedName("0")
    UNKNOWN_TYPE,
    @SerializedName("11")
    SIMPLE_TYPE,
    @SerializedName("42")
    COMPLEX_TYPE
  }

You can just use the @SerializedName annotation to determine what value gets serialized to/from the wire. Then you don't need to write a custom TypeAdapter.

import com.google.gson.annotations.SerializedName;

public enum ObjectTypeEnum {
    @SerializedName("0")
    UNKNOWN_TYPE(0),

    @SerializedName("11")
    SIMPLE_TYPE(11),

    @SerialziedName("42")
    COMPLEX_TYPE(42);

    private int value;

    private ObjectTypeEnum(int value) {
        this.value = value;         
    }

    public int getValue() {
        return value;
    }
}

If you don't have a need for getting the wire value in your code you can eliminate the "value" field and related code.

public enum ObjectTypeEnum {
    @SerializedName("0")
    UNKNOWN_TYPE,

    @SerializedName("11")
    SIMPLE_TYPE,

    @SerialziedName("42")
    COMPLEX_TYPE;
}

Using an answer from Chin and help from my workmate I get following solution.

I wrote an inner class in the parser class.

private static class ObjectTypeDeserializer implements
        JsonDeserializer<ObjectTypeEnum>
{
    @Override
    public PreconditioningStatusEnum deserialize(JsonElement json,
            Type typeOfT, JsonDeserializationContext ctx)
            throws JsonParseException
    {
        int typeInt = json.getAsInt();
        return ObjectTypeEnum
                .findByAbbr(typeInt);
    }
}

and created GSON-Object on following way:

    GsonBuilder gsonBuilder = new GsonBuilder();
    gsonBuilder.registerTypeAdapter(ObjectTypeEnum.class, new ObjectTypeDeserializer() );
    Gson gson = gsonBuilder.create();

http://sites.google.com/site/gson/gson-user-guide#TOC-Custom-Serialization-and-Deserializ