How to generate swagger.json from gradle task?

[Velmurugan Velayutham]

I have integrated swagger-core with my project and I am able to access the swagger.json response successfully. However I was asked to generate the swagger.json as part of gradle task. I do not want to specify any swagger related servlets in the web.xml.
ApiListingResource - is responsible for producing swagger.json and swagger.yaml responses.
Is there any gradle plugin which does this work?. If so , Can you give me an reference to it?

Thanks...