Package org.apache.struts.extras.actions

Class LookupDispatchAction

java.lang.Object
org.apache.struts.action.Action
org.apache.struts.extras.actions.BaseAction
org.apache.struts.extras.actions.DispatchAction
org.apache.struts.extras.actions.LookupDispatchAction
All Implemented Interfaces:
Serializable
public abstract class LookupDispatchAction extends DispatchAction

An abstract Action that dispatches to the subclass mapped execute method. This is useful in cases where an HTML form has multiple submit buttons with the same name. The button name is specified by the parameter property of the corresponding ActionMapping. To configure the use of this action in your struts-config.xml file, create an entry like this:

   <action path="/test"
           type="org.example.MyAction"
           name="MyForm"
          scope="request"
          input="/test.jsp"
      parameter="method"/>

which will use the value of the request parameter named "method" to locate the corresponding key in ApplicationResources. For example, you might have the following ApplicationResources.properties:

    button.add=Add Record
    button.delete=Delete Record

And your JSP would have the following format for submit buttons:

   <html:form action="/test">
    <html:submit property="method">
      <bean:message key="button.add"/>
    </html:submit>
    <html:submit property="method">
      <bean:message key="button.delete"/>
    </html:submit>
  </html:form>

Your subclass must implement both getKeyMethodMap and the methods defined in the map. An example of such implementations are:

  protected Map getKeyMethodMap() {
      Map map = new HashMap();
      map.put("button.add", "add");
      map.put("button.delete", "delete");
      return map;
  }

  public ActionForward add(ActionMapping mapping,
          ActionForm form,
          HttpServletRequest request,
          HttpServletResponse response)
          throws IOException, ServletException {
      // do add
      return mapping.findForward("success");
  }

  public ActionForward delete(ActionMapping mapping,
          ActionForm form,
          HttpServletRequest request,
          HttpServletResponse response)
          throws IOException, ServletException {
      // do delete
      return mapping.findForward("success");
  }

Notes - If duplicate values exist for the keys returned by getKeys, only the first one found will be returned. If no corresponding key is found then an exception will be thrown. You can override the method unspecified to provide a custom handler. If the submit was cancelled (a html:cancel button was pressed), the custom handler cancelled will be used instead.

See Also:

  • Field Details

    • localeMap

      protected HashMap<Locale,Map<String,String>> localeMap
      Reverse lookup map from resource value to resource key.

    • keyMethodMap

      protected Map<String,String> keyMethodMap
      Resource key to method name lookup.

  • Constructor Details

    • LookupDispatchAction

      public LookupDispatchAction()

  • Method Details

    • execute

      public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception
      Process the specified HTTP request, and create the corresponding HTTP response (or forward to another web component that will create it). Return an ActionForward instance describing where and how control should be forwarded, or null if the response has already been completed.
      Overrides:
      execute in class DispatchAction
      Parameters:
      mapping - The ActionMapping used to select this instance
      form - The optional ActionForm bean for this request (if any)
      request - The HTTP request we are processing
      response - The HTTP response we are creating
      Returns:
      Describes where and how control should be forwarded.
      Throws:
      Exception - if an error occurs

    • getKeyMethodMap

      protected abstract Map<String,String> getKeyMethodMap()
      Provides the mapping from resource key to method name.
      Returns:
      Resource key / method name map.

    • getLookupMapName

      protected String getLookupMapName(HttpServletRequest request, String keyName, ActionMapping mapping) throws ServletException
      Lookup the method name corresponding to the client request's locale.
      Parameters:
      request - The HTTP request we are processing
      keyName - The parameter name to use as the properties key
      mapping - The ActionMapping used to select this instance
      Returns:
      The method's localized name.
      Throws:
      ServletException - if keyName cannot be resolved
      Since:
      Struts 1.2.0

    • getMethodName

      protected String getMethodName(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response, String parameter) throws Exception
      Returns the method name, given a parameter's value.
      Overrides:
      getMethodName in class DispatchAction
      Parameters:
      mapping - The ActionMapping used to select this instance
      form - The optional ActionForm bean for this request (if any)
      request - The HTTP request we are processing
      response - The HTTP response we are creating
      parameter - The ActionMapping parameter's name
      Returns:
      The method's name.
      Throws:
      Exception - if an error occurs
      Since:
      Struts 1.2.0