NonStop Servlets for JavaServer Pages (5.0) System Administrator's Guide

Migrating to NSJSP 5.0
NonStop Servlets for JavaServer Pages (NSJSP) System Administrator’s Guide—525644-002
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Changes from Servlet 2.3 to Servlet 2.4
Filters are configured such that they are invoked on RequestDispatcher
include() and forward() calls. Use the <dispatcher> sub-element under
the <filter-mapping> element in the deployment descriptor web.xml.
For example, the following code configures filter mapping whereby a filter named
"my Forward Filter" is invoked when the request being processed under a
RequestDispatcher matches the <url-pattern> for a forward() call.
<filter-mapping>
<filter-name>my Forward Filter</filter-name>
<url-pattern>/myApp/*</url-pattern>
<dispatcher>FORWARD</dispatcher>
</filter-mapping>
Supported values in the <dispatcher> sub-element include one or more
combinations of REQUEST, INCLUDE, FORWARD, and ERROR.
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New HttpSessionListener events for session migration and for Object binding.
New HttpSession event methods have been added for session migration
(activation and passivation of Sessions) and for Object binding (bind and unbind
operations) using the HttpSessionActivationListener and
HttpSessionBindingListener interfaces. In addition, a new
HttpSessionBindingEvent has been defined.
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The HttpSessionListener.sessionDestroyed() event is now notified
before the session is invalidated (and not after the session is invalidated as in
previous API specifications).
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Support for event notifications about state changes in the ServletRequest objects.
The Java Servlet 2.4 API specification also adds new Listener interfaces and Event
classes to allow notifications of request lifecycle events and events for changes to
request attributes. The ServletRequestListener and
ServletRequestAttributeListener are the two new Listener interfaces, and
the ServletRequestEvent and ServletRequestAttributeEvent are their
corresponding event classes. Request lifecycle events are defined when the
request is about to enter the first servlet or filter and when the request exits the last
servlet or filter in the application filter chain for any web application.
Some exceptions thrown in the Listener interfaces have an adverse impact on
subsequent requests to a particular web application. For example, unhandled
exceptions thrown when a ServletContextListener gets a servlet context
initialization notification or when a ServletRequestListener gets a request
initialization/destruction event or when a SessionListener gets a session
timeout event.
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The HttpSession.logout() method (added in an intermediate version of the
Java Servlet 2.4 API specification) has been removed and will be addressed in the
next version.