Web fragments, a new feature of Servlet 3.0 technology, solves this problem by modularizing deployment descriptors.
Web fragments, a new feature of Servlet 3.0 technology, solves this problem by modularizing deployment descriptors. A web fragment can be considered a logical segment of a web.xml file. There can be multiple web fragments, each representing a logical segment, and the set of web fragments can be viewed as constituting an entire web.xml file.
Docs: http://www.oracle.com/technetwork/articles/javaee/javaee6overview-part2-136353.html#webfrags