You can add a filter to a web application deployment descriptor (web.xml)
in two ways:
Using the New Filter wizard when you create the filter.
On the Configure Filter Deployment page, select the Add information to deployment
descriptor (web.xml) checkbox, type the filter's internal name, and add the
filter's mappings. Optionally, you can add the filter's initialization parameters
from the Filter Init Parameters page, which is the next step in the wizard.
The filter element defines a filter in the deployment descriptor.
Filter class instances are scoped to one filter
per deployment descriptor declaration per Java virtual machine.
For more information about filters, see the Java Servlet Specification
available at