This is an SCM plugin for HudsonJenkins. While URLs are not actually a proper SCM, the two main behaviors of an SCM are supported - checkout and polling. Polling is accomplished by checking the last-modified property of the URL. Checkout is accomplished by copying the content of the URL into the workspace as a file. The file is given the same name as the final filename component of the URL. URLs without a filename component cannot be used at this time.
This does duplicate some of what the URLChange Trigger plugin does.
Benefits of URLChange Trigger over this plugin:
1. Hudson Jenkins only supports one SCM plugin per project. If you want to trigger an SCM checkout via a URL, then URLChange Trigger is a better choice.
2. The last-modified property of a URL is not the right trigger for your builds, instead you need the content of the URL to change to trigger a build.