You can use x headers to detect if the URL is using HTTP or HTTPS, you will find the header x-https only exists in the GetHttpRequestData() method when using HTTPS. Below is a simple IF statement to detect this:
<cfif StructKeyExists(GetHttpRequestData().headers, 'x-https')>
HTTPS
<cfelse>
HTTP
</cfif>
Seeing all x headers:
You can use the following code to dump call request headers that tomcat proxy will detect:
<cfdump(GetHttpRequestData())>