public class EventDispatchAction extends DispatchAction
An Action that dispatches to to one of the public methods
that are named in the parameter
attribute of the corresponding
ActionMapping and matches a submission parameter. This is useful for
developers who prefer to use many submit buttons, images, or submit links
on a single form and whose related actions exist in a single Action class.
The method(s) must have the same signature (other than method name) of the standard Action.execute method.
To configure the use of this action in your
struts-config.xml
file, create an entry like this:
<action path="/saveSubscription"
type="org.example.SubscriptionAction"
name="subscriptionForm"
scope="request"
input="/subscription.jsp"
parameter="save,back,recalc=recalculate,default=save"/>
where parameter
contains three possible methods and one
default method if nothing matches (such as the user pressing the enter key).
For utility purposes, you can use the key=value
notation to
alias methods so that they are exposed as different form element names, in the
event of a naming conflict or otherwise. In this example, the recalc
button (via a request parameter) will invoke the recalculate
method. The security-minded person may find this feature valuable to
obfuscate and not expose the methods.
The default key is purely optional. If this is not specified
and no parameters match the list of method keys, null
is
returned which means the unspecified
method will be invoked.
The order of the parameters are guaranteed to be iterated in the order specified. If multiple buttons were accidently submitted, the first match in the list will be dispatched.
clazz, log, methods, types
messages
Constructor and Description |
---|
EventDispatchAction() |
Modifier and Type | Method and Description |
---|---|
protected String |
getMethodName(ActionMapping mapping,
ActionForm form,
javax.servlet.http.HttpServletRequest request,
javax.servlet.http.HttpServletResponse response,
String parameter)
Returns the method name, given a parameter's value.
|
protected ActionForward |
unspecified(ActionMapping mapping,
ActionForm form,
javax.servlet.http.HttpServletRequest request,
javax.servlet.http.HttpServletResponse response)
Method which is dispatched to when there is no value for specified
request parameter included in the request.
|
cancelled, dispatchMethod, execute, getMethod, getParameter
addErrors, addMessages, execute, generateToken, getErrors, getLocale, getMessages, getResources, getResources, getServlet, isCancelled, isTokenValid, isTokenValid, resetToken, saveErrors, saveErrors, saveMessages, saveMessages, saveToken, setLocale, setServlet
protected ActionForward unspecified(ActionMapping mapping, ActionForm form, javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws Exception
DispatchAction
should override this method if they wish to
provide default behavior different than throwing a ServletException.unspecified
in class DispatchAction
mapping
- The ActionMapping used to select this instanceform
- The optional ActionForm bean for this request (if any)request
- The non-HTTP request we are processingresponse
- The non-HTTP response we are creatingnull
if the response has been completed.Exception
- if the application business logic throws an
exception.protected String getMethodName(ActionMapping mapping, ActionForm form, javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response, String parameter) throws Exception
getMethodName
in class DispatchAction
mapping
- The ActionMapping used to select this instanceform
- The optional ActionForm bean for this request (if
any)request
- The HTTP request we are processingresponse
- The HTTP response we are creatingparameter
- The ActionMapping
parameter's nameException
- if an error occurs.Copyright © 2000–2017 Apache Software Foundation. All rights reserved.