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Wildcard Method

Many times, a set of action mappings will share a common pattern. For example, all your edit actions might start with the word "edit", and call the edit method on the Action class. The delete actions might use the same pattern, but call the delete method instead.

Rather than code a separate mapping for each action class that uses this pattern, you can write it once as a wildcard mapping.

<action name="*Crud" class="example.Crud" method="{1}">

Here, a reference to "editCrud" will call the edit method on an instance of the Crud Action class. Likewise, a reference to "deleteCrud" will call the delete method instead.

Another common approach is to postfix the method name and set it off with an exclamation point (aka "bang"), underscore, or other special character.

• "action=Crud_input"
• "action=Crud_delete"

To use a postfix wildcard, just move the asterisk and add an underscore.

<action name="Crud_*" class="example.Crud" method="{1}">

From the framework's perspective, a wildcard mapping creates a new "virtual" mapping with all the same attributes as a conventional, static mapping. As a result, you can use the expanded wildcard name as the name of validation, type conversion, and localization files, just as if it were an Action name (which it is!).

• Crud_input-validation.xml
• Crud_delete-conversion.xml

The postfix "!" notation is also available in WebWork 2, but it is implemented differently. To use the old implementation, set struts.enable.DynamicMethodInvocation=TRUE in the struts.properties file. To use wildcards instead (preferred), set struts.enable.DynamicMethodInvocation=FALSE.