Can we use regular expressions in web.xml URL patterns?

Satya picture Satya · Dec 20, 2011 · Viewed 58.8k times · Source

I am writing a filter to do a specific task but I am unable to set a specific url pattern to my filter. My filter mapping is as follows:

 <web.xml>
  <filter>
     <filter-name>myFilter</filter-name>
     <filter-class>test.MyFilter</filter-class>
   </filter>

  <filter-mapping>
    <filter-name>myFilter</filter-name>
     <url-pattern>/org/test/*/keys/*</url-pattern>
   </filter-mapping>
 </web-app>

My url-pattern [ /org/test/ * /keys/ * ] is not working as I had expected.

I am calling urls from the browser like:

http://localhost:8080/myapp/org/test/SuperAdminReport/keys/superAdminReport.jsp
http://localhost:8080/myapp/org/test/Adminreport/keys/adminReport.jsp
http://localhost:8080/myapp/org/test/OtherReport/keys/otherReport.jsp

So for the URLs above the filter pattern should match. How can I achieve this?

Answer

Stephen C picture Stephen C · Dec 20, 2011

No, you can't use a regex there. According to the Java Servlet Specification v2.4 (section srv.11.1), the url-path is interpreted as follows:

  • A string beginning with a ‘/’ character and ending with a ‘/*’ suffix is used for path mapping.
  • A string beginning with a ‘*.’ prefix is used as an extension mapping.
  • A string containing only the ’/’ character indicates the "default" servlet of the application. In this case the servlet path is the request URI minus the con- text path and the path info is null.
  • All other strings are used for exact matches only.

No regexes are allowed. Not even complicated wild-cards.