Question

I have seen many tutorials in which action has many methods other than execute

public class UserAction {

    public TestAction() {
    }

    public String execute() throws Exception {
      System.out.println("hello i aam action");

        return "success";
    }

    public String addUser(String name)
    {

     return "success";


   }

    public String listUser(String name)
    {

     return "success";


    }

    }

the action mapping is done like this

  <action name="addUser" method="addUser" class="com.vaannila.web.UserAction">
  <result name="success" type="redirect">listUser</result>
</action>

<action name="listUser" method="listUser" class="com.vaannila.web.UserAction"> 
  <result name="success">/register.jsp</result>
 </action>

I a unable to understand it.How listUser is getting called?

Answer 1

I don’t think this works because your mapping is pointing to methods (add, list) that do not exist. You have addUser and listUser in your action so your mapping have to point to the same methods.
Back to your question I have to say Struts2 has a feature that let’s you pack a couple of methods into the same action. This is specially useful when you want to perform CRUD operations. One way is to explicitly predetermine the method you want to call in you mapping:

<action name="listUser" method="list" class="com.vaannila.web.UserAction"> 
    <result name="success">/register.jsp</result>
</action>

If you point your browser to http://yourDomainHere/listUser your list method in your UserAction action will be executed. You can also use wildcard mapping here like:

<action name="*User" method="{1}" class="com.vaannila.web.UserAction"> 
    <result name="success">/register.jsp</result>
</action>

In this case you can replace asterisk (*) with any method in your action. This mapping will take first placeholder ({1}) in the mapping as a method and call it. So you can point your browser to: http://yourDomainHere/listUser and http://yourDomainHere/addUser knowing the same mapping will handle both and your respective methods will be called.

Edit for the comment
I think I got your point. In the example you provided listCustomer is never called. It’s the addCustomer that populates the customerList before sending success and since it has provided a getter method for the list, back in the page you can access it and iterate it and show the values.