How to find the IP address of an amazon EC2 instance on reboot

Question

On reboot, the IP address of an amazon instance changes. How to find the new IP address using java API?

Answer 1

Assuming you don't want to assign an Elastic IP address (and there are reasons why this is not always a solution) then simply call DescribeInstances on the rebooted instance, which returns a bunch of information including Public IP Address.

Here's the AWS EC2 Java API Documentation on the topic.