Excluding certain fields from Serialization based on value in GSON

Question

I am using GSON for my serialization purposes, I am not finding a way of excluding certain fields from serialization based on ExclusionStrategy class provided by Gson based

Answer 1

The way to achieve this is by creating custom serializer for the class in question. After allowing Gson to create a JSON object in default fashion, remove the property that you want to exclude based on its value.

public class SerializerForMyClass implements JsonSerializer {  

    @Override
    public JsonElement serialize(MyClass obj, Type type, JsonSerializationContext jsc) {
        Gson gson = new Gson();
        JsonObject jObj = (JsonObject)gson.toJsonTree(obj);   
        if(obj.getMyProperty()==0){
            jObj.remove("myProperty");
        }
        return jObj;
    }
}

And registering the new serializer in the Gson object that you use for serialization in the application for this class.

GsonBuilder gsonBuilder = new GsonBuilder();
gsonBuilder.registerTypeAdapter(MyClass.class, new SerializerForMyClass());
Gson gson=gsonBuilder.create();
gson.toJson(myObjectOfTypeMyClass);