inversion of control (ioc) tutorials

Resources are beans configured in the resin.conf or resin-web.xml and stored in the WebBeans registry. The tutorial shows the configuration of a trivial bean as a resource and using it from a JSP file.

The Dependency Injection pattern simplifies application code, and increases configuration flexibility by deferring component configuration and assembly to the container. Resin calls setters on the configured objects to assemble the resource dependencies.

This tutorial demonstrates the creation of a PeriodicTask that performs a task at intervals and collects statistics on it's performance. An administration interface to the task is provided, and while the task is active the user is shown a "temporarily unavailable" page.

The code for this tutorial provides a full featured example that can be used as a cut-and-paste source for solving real problems. The PeriodicTask keeps detailed statistics, an administration interface is provided with a servlet, and the task can be executed either manually or automatically at timed intervals.

Applications often need to read, and possibly write, configuration files. An excellent way to accomplish this is to implement a custom singleton, which is easily configured and easily obtained from anywhere in the application.

This implementation of the concept allows you to configure a base directory for configuration files. An object of type AppConfig is obtained with a javax.webbeans.In injection. It is used to open files relative to the base directory.