Prior to Liberty 22.0.0.1, the Liberty server cannot load web modules where the web.xml deployment descriptor has a namespace value that does not match the defined version. Web modules at version 2.4 must use the http://java.sun.com/xml/ns/j2ee namespace. Web modules at version 2.5 or 3.0 must use the http://java.sun.com/xml/ns/java namespace. Web modules at version 3.1 to 4.0 must use the http://xmlns.jcp.org/xml/ns/javaee namespace. Web modules at version 5.0 or later must use the https://jakarta.ee/xml/ns/jakartaee namespace.

This requirement for the Liberty server was removed in Liberty 22.0.0.1. Namespace values in the web.xml do not need to match the defined versions in Liberty 22.0.0.1 and later versions.

This rule has an automated fix to update the namespace value. Copy the custom configuration to your application build file to enable it.