ZK Developer's Guide

Getting Started with ZK
Separation of Concerns
One important paradigm in object-oriented programming is Separation of Concerns
(SoC). This paradigm says that an application should be broken into distinct features
that overlap in functionality as little as possible (see http://en.wikipedia.org/
wiki/Separation_of_concerns).
For large applications, it's not advisable to do the layout, and the logic together in
one page. For such applications, you should follow the programming principle of
separation of concerns. This separation is not only for architecture, but also for better
maintenance of your application. This is because if you have your logic directly in
Java classes, you can leverage the full power of your IDE, e.g. you can have a good
debugger, and you can easily write unit tests.
Configuration and Deployment
The configuration for the ZK framework is separated in two files: web.xml for servlet
and mapping definition, and zk.xml, which gives the possibility of overriding
the default ZK system settings. The following figure shows that there are some
mandatory settings, and some optional additional settings. The configuration in
web.xml is mandatory for correct working of the ZK framework.
Configuration of web.xml
The most important place to configure a web application is the web.xml file. Without
correct settings nothing will work. In the next paragraphs, we will have a detailed
look at the settings that are necessary for the ZK framework.
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