It is very simple process using iptables firewall.
Below is a single step.
# iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-port 8443
All request coming on port 443 are forwarded to Port 8443 of Tomcat.
Check this using Url in browser as below.
https://demo.ssharad.com
This should show Default Page of Tomcat as below.
