Parsing state in episodes from YAML file

[Gautam]

Hello all,
I am creating a 3D domain with BURLAP 3, where the agent is in a 2D grid world but its pose is in 3 dimensions (x, y, theta). It is a new set of classes that are children of the corresponding grid world files (GridWorldDomain, GridAgent, GridWorldState, etc.)

Here is an example of the custom domain with custom deterministic actions that I have created:
https://drive.google.com/file/d/1MjupIzGSDLrfFbRkD8piwzy7jX5HeWkT/view?usp=sharing

However, when I record episodes in this domain, the generated YAML files cannot be read by the episode parser. Specifically, this is the error I get, when I run the episode playback tool and click on an episode

_______________
null; Can't construct a java object for tag:yaml.org,2002:Tutorial.XYThetaState; exception=null; in 'string', line 9, column 3:
- !!Tutorial.XYThetaState
^
_______________

I am not well-versed with YAML, so any help on what I need to add to my new class XYThetaState would be appreciated!! (XYThetaState is a child of BURLAPs GridWorldState)

[Gautam]

Update: I created my own Grid classes by implementing the interfaces directly instead of inheriting from the BURLAP GridWorld example. This solved my problem.