How to use object retrieved from http task in flowable

I have made a call to rest API using Htttp task service available in flowable

Request URL = http://localhost:3000/getEmployee/4

it was supposed to return me a Object of Employee Class with id =4
*I have checked the call is made
*also object with id=4 is also present in database

How can I use this object in Flowable because I am using employee.isPresent( a Boolean variable in making decision in exclusive gateway)

How can I use isPresent property of Employee Object in making decision in exclusive gateway
Thanks in advance

Solved.You have to use task id as prefix.