ContextLoader and FrameworkServlet now use
AnnotationAwareOrderComparator to support @Order usage; previously
supported only implementation of the Ordered interface.
Constructors have been added to both FrameworkServlet and
DispatcherServlet to support instance-based programmatic registration
of Servlets within ServletContainerInitializer implementations in
Servlet 3.0+ environments, and more particularly when using Spring 3.1's
WebApplicationInitializer SPI.
This change also renames the method added to FrameworkServlet in
SPR-8185 from #initializeWebApplicationContext to #applyInitializers.
The reason being that a method named #initWebApplicationContext was
already present and the names overlapped confusingly.
Issue: SPR-7672, SPR-8185
Calls to AbstractApplicationContext#setParent delegate the parent
context environment to the child.
This ensures that any property sources added to the parent are available
to the child as well as ensuring that any profiles activated are
activated everywhere.
Child contexts may still choose to replace their environment (through an
ApplicationContextInitializer, for example). In any case, however, in
the root/child web application context relationship established by
ContextLoader + DispatcherServlet, the child is guaranteed to have
already been given the parent environment by the time it is delegated
to any ACIs.
See AbstractApplicationContext#setParent for implementation
See FrameworkServlet#createWebApplicationContext for order in which
setParent then initializeWebApplicationContext are called.
Issue: SPR-8185
FrameworkServlet now has support equivalent to ContextLoader and its
"contextInitializerClasses" context-param introduced in 3.1 M1.
This allows users to specify ApplicationContextInitializers at the root
(ContextLoader) level and/or at the DispatcherServlet level.
Issue: SPR-8366
Rossen Stoyanchev
Chris Beams
Arjen Poutsma