It takes more than 5 minutes for your tomcat to startup. You think it’s your application’s program. But when you download a clean Tomcat (of the same version) can run it without dropping in any of your applications, it still gets stuck.
It may be caused by this: https://wiki.apache.org/tomcat/HowTo/FasterStartUp#Entropy_Source
According to my just wasted 2 hours, it can be true and solution presented on it will work.