To generate real time alerts

As part of a project I have to present architecture…I have below scenarios:

  1. We have a data storage which collects every milliseconds GPS data of an moving object like a car
  2. We need to stream that real time data into Hbase database
  3. Generate notifications if an object moves out of specified zone like if a car leaves a specified town then a rental office manager should be notified.
  4. We have to implement this using hadoop cluster and we have to use tools like spark, Hbase and Kafka

However, I am stuck at 3rd point. How can I generate real time alerts in hadoop with specified tools? Or is there any other better tool available which I can use so that my project will be more effective.

Please help.