Simple Command

Exactly the same as SimpleMVC except the controller actions have been factored out to separate classes. This is a simple implementation of the "Command" or "Action" pattern. Using this pattern allows you to process all of your web actions from one controller servlet; eliminating the need for redundant code and long deployment descriptors.

There are several variations of this pattern. With this one, the request and command objects are passed to the command object. The proper command object is determined by examining the form parameter "form_action".

The commands are instanciated and loaded into the map from the servlet's init method. In this case the command's name and class are hardcoded right in the servlet's java file. Most frameworks factor this out to a separate config file which allows you to add commands without needing to change and recompile the controller servlet.

To Run:

  1. Download SimpleCommand.war to your TOMCAT_INSTALL/webapps directory.
    If you're using MSIE, make sure it doesn't change the extension to ".zip".
  2. Then, click on this link:
    http://localhost:8080/SimpleCommand