Preventing infinite recursion caused by circular references

[lalpert]

Jackson has a solution to serializing classes with bidirection references using @JsonIdentityInfo (For example, see http://www.baeldung.com/jackson-bidirectional-relationships-and-infinite-recursion#json-identity-info). This way, you can serialize either object, and rather than causing a stack overflow error, it will just include a reference back to the object already included in the serialization. It seems like Gson does not have a solution like that. Could that be added to gson-fire?

[julman99]

Thanks for your suggestion, I will try to include this or something similar in 1.8.0 which I will be released around mid-oct.

[Typografikon]

Any progress with this issue? Is there some solution to handle cyclic reference and avoid stack overflow (other than remove one side of bidirectional reference)?

Thanks!

[interappcci]

Is there some update about that? I've been looking for a elegant solution to this since ever and nothing found. For while..

[julman99]

Sorry I've been super busy and lost track of this. I'll think about something based on what @lalpert suggested and will reply back here before the end of the week with a timeline.

[julman99]

Would it work if I create an annotation to override the type adapter of a particular field in a class? For example

public class Person {
    private int id;
    private String name;
    private House house;
}

public class House {
    @TypeAdapter(SimplePersonAdapter.class)
    private Person owner;
}

public class SimplePersonAdapter implements TypeAdapter<Person> {
     //this class just serializes a simplified version of a Person object, for example it could just serialize the id
}

[julman99]

@interappcci, @lalpert I think I will include my suggestion in my previous comment since it solves also a different requirement that was raised to me the other day.

Does that work for both of you in regards to the circular reference problem?

[aninfeel]

I just need to cxclude a field at the second nested while serializing a object:

class User {
   String name;
   User createdBy;
}

class JsonRespWrap<D> {
   int code;
   User data;
  public JsonRespWrap (D data ) {
    this.data = data
    this.code = 0
  }
}

User user = userDao.findOne(1)

gson.toJson(new JsonRespWrap(user)); //  data.createdBy.createdBy should be excluded but data.createdBy should be included

// here is the exclusion stratety

public class GsonExclusionStrategy implements ExclusionStrategy{
   //...

    @Override
    public boolean shouldSkipClass(Class<?> clazz) {
        return true;
    }

    @Override
    public boolean shouldSkipField(FieldAttributes f) {
        //how to do whthout parent FieldAttributes (or a stack of FieldAttributeses) provided as parameter
    }
}