How to catch exceptions generated by packages in Laravel 5?

I am working with a package called tymondesigns/jwt-auth in Laravel 5 and it generates exceptions like TokenExpiredException, TokenInvalidException and so on. I would like to catch these exceptions and return JSON responses for them. I have tried this in the Handler.php file:

if ($e instanceof TokenExpiredException) {
    return jsend()->error()
              ->message("Token has Expired")
              ->data([null])
              ->get();
}

But in vain. How to catch these exceptions and return JSON responses?

via Chebli Mohamed