Java Reference
In-Depth Information
It is possible to chain view resolvers in case a single resolver is insufficient for the
application. The view resolver chaining works in a similar way to the handler mapping
chain because most of the view resolvers implement the
Ordered
interface.
Consequences
Benefits
•
Enhanced modularity
: Partitioning view and command management into two
distinct and decoupled subsystems makes an application modular and robust.
•
Increased reusability
: The application controller makes it possible to reuse the
controllers and views.
•
Increased extensibility
: The Spring application controller's various interfaces and
abstract base classes with template methods make it easy to extend the framework,
supporting a variety of command controllers and views. It is also possible to inte-
grate third-party action-based web frameworks such as WebWork, Struts, and so
on, with Spring MVC as well as work with views such as OpenLaszlo and Flex.
Concerns
•
Steep learning curve
: Ideally, the application controller should be a low-level
framework concern. For most common needs, you will generally not work with the
application controller because Spring has sensible defaults. However, it also throws
this component wide open for developers seeking extensibility and flexibility. This
adds to the learning curve because you now need to know a lot more about frame-
work internals to support exceptional requirements.
Page Controller
Problem
The JSP-based controller introduced at the beginning of this chapter handled each user
action by executing code in
if-else
blocks. Each
if-else
block was responsible primarily
