Please elaborate on, "url-pattern... unique to world"

[Al Johnson]

This question is in reference to Atlassian Developer Documentation: Servlet Filter Module

Can anyone elaborate on this note in the above page?

Because servlet filters are deployed beneath root, be careful when choosing each url-pattern under which your filter is deployed. If you plan to handle the request in the filter, it is recommended to use a value that will always be unique to the world! 

Thanks

[Panos]

I means that servlet will do pattern matching and will be recursive. If you use for example /display/* then all urls under /display will be filtered no matter how much nested they are.

[Al Johnson]

Have no idea what you are saying.  Most everyone knows that URL endpoints have to be unique, so I'm assuming they mean something more than that.