Using Tomcat, @WebFilter doesn't work with inside web.xml

Question

Here\'s a working web.xml:

Answer 1

It's a bug in Tomcat 7. I reported it as issue 53354.

As it's not possible to specify the invocation order in a @WebFilter, users are forced to explicitly specify <filter-mapping> in web.xml. This works in combination with a @WebFilter(filterName) in Glassfish and JBoss AS as follows:

@WebFilter(filterName="filter1")
public class Filter1 implements Filter {}

@WebFilter(filterName="filter2")
public class Filter2 implements Filter {}

with

<filter-mapping>
    <filter-name>filter1</filter-name>
    <url-pattern>/url1/*</url-pattern>
</filter-mapping>
<filter-mapping>
    <filter-name>filter2</filter-name>
    <url-pattern>/url2/*</url-pattern>
</filter-mapping>

However it fails in Tomcat 7.0.27 with the following confusing exception (the <url-pattern> is been set)

Caused by: java.lang.IllegalArgumentException: Filter mapping must specify either a <url-pattern> or a <servlet-name>
    at org.apache.catalina.core.StandardContext.validateFilterMap(StandardContext.java:3009)
    at org.apache.catalina.core.StandardContext.addFilterMap(StandardContext.java:2968)
    at org.apache.catalina.deploy.WebXml.configureContext(WebXml.java:1207)
    at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1294)
    at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:855)
    at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:345)
    at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5161)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    ... 7 more

In the meanwhile your best bet is to use Glassfish or JBoss AS instead, or to register the filters by <filter> anyway.

Answer 2

You must specify a target for the Servlet Filter. Either provide a value for 'servletNames' or 'urlPatterns'.

http://docs.oracle.com/javaee/6/api/javax/servlet/annotation/WebFilter.html

e.g.

@WebFilter(filterName="mustBeSignedInFilter", urlPatterns={ "/signed/in/path/*" })
public class MustBeSignedInFilter implements Filter