Start server
./gradlew run
Run
curl localhost:8080/test
which shows a html that belongs to google com
Now get the ip address for bing, eg
ping www.bing.com
and update your hosts file to point www.google.com to bing
vi /etc/hosts
eg
204.79.197.200 www.google.com
Now rerun after the dns cache times out (approx 60 seconds)
curl localhost:8080/test
and u see that there is still results from www.google.com that is returned. If you try to fetch www.google.com directly (curl www.google.com from the command line) you'll get a page that belongs to Bing, as expected.
However, if client pooling is disabled, a new dns lookup is made after the dns ttl, and different content is returned.