Java Doc for ActionDispatcher.java in  » Web-Framework » struts-1.3.8 » org » apache » struts » actions » Java Source Code / Java DocumentationJava Source Code and Java Documentation

Action helper class that dispatches to a public method in an Action.

This class is provided as an alternative mechanism to using DispatchAction and its various flavours and means Dispatch behaviour can be easily implemented into any Action without having to inherit from a particular super Action.

To implement dispatch behaviour in an Action class, create your custom Action as follows, along with the methods you require (and optionally "cancelled" and "unspecified" methods):

 public class MyCustomAction extends Action {
 protected ActionDispatcher dispatcher
 = new ActionDispatcher(this, ActionDispatcher.MAPPING_FLAVOR);
 public ActionForward execute(ActionMapping mapping,
 ActionForm form,
 HttpServletRequest request,
 HttpServletResponse response)
 throws Exception {
 return dispatcher.execute(mapping, form, request, response);
 }
 }
 

It provides three flavours of determing the name of the method:

• ActionDispatcher.DEFAULT_FLAVOR - uses the parameter specified in the struts-config.xml to get the method name from the Request (equivalent to DispatchAction except uses "method" as a default if the parameter is not specified in the struts-config.xml).
• ActionDispatcher.DISPATCH_FLAVOR - uses the parameter specified in the struts-config.xml to get the method name from the Request (equivalent to DispatchAction).
• ActionDispatcher.MAPPING_FLAVOR - uses the parameter specified in the struts-config.xml as the method name (equivalent to MappingDispatchAction).

Dispatches to the target class' cancelled method, if present, otherwise returns null.

Returns true if the current form's cancel button was pressed.

Dispatches to the target class' unspecified method, if present, otherwise throws a ServletException.

Dispatches to the target class' cancelled method, if present, otherwise returns null. Classes utilizing ActionDispatcher should provide a cancelled method if they wish to provide behavior different than returning null.

Returns the parameter value as influenced by the selected ActionDispatcher.flavor specified for this ActionDispatcher.

Returns true if the current form's cancel button was pressed. This method will check if the Globals.CANCEL_KEY request attribute has been set, which normally occurs if the cancel button generated by CancelTag was pressed by the user in the current request. If true, validation performed by an ActionForm's validate() method will have been skipped by the controller servlet.

Dispatches to the target class' unspecified method, if present, otherwise throws a ServletException. Classes utilizing ActionDispatcher should provide an unspecified method if they wish to provide behavior different than throwing a ServletException.