Velocity Template Language
Velocity is a Java-based template engine. 
It permits anyone to use a simple yet powerful template language to reference objects defined in Java code.

below vms is for opensaml
add-html-body-content.vm
add-html-head-content.vm
saml1-post-binding.vm
saml2-post-artifact-binding.vm
saml2-post-binding.vm
saml2-post-simplesign-binding.vm