Check all outgoing calls of a web application

I have a tomcat based web application here and I need to make sure that the libraries used are not making any calls to outside web sites. For example our sencha lib is calling home. But there might be also others. Therefor my idea was to run a network monitoring tool on the linux server to create a statistic about all outgoing http requests.

The tomcat is running on a CENTOS 7 server.

www.google.de      20 calls
www.stackoverflow  30 calls

I tried tcpflow and grepped the output. It works but it is too detailed. And I need to spend time to aggregate the data by my self.

 sudo tcpflow -p -c -i ens192 port 80 |grep "Host:"

Is there a more simple tool that does the job?