java strtus2 DynamicMethodInvocation配置入门

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
    xmlns="http://java.sun.com/xml/ns/javaee" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
    http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
  <display-name></display-name>    
  
  <filter>
      <filter-name>struts2</filter-name>
      <!-- 可在引用的jar包struts2-core-2.3.15.3.jar下的 org.apache.struts2.dispatcher.ng.filter找到-->
      <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
  </filter>
  <filter-mapping>
      <filter-name>struts2</filter-name>
      <url-pattern>/*</url-pattern>
  </filter-mapping>
  
</web-app>

    <package name="Menu" namespace="/Menu" extends="struts-default">
       <action name="mainpage" class="com.almostman.action.MainPageAction">
         <result name="success">/success.jsp</result>
         <result name="input">/input.jsp</result>
       </action>
    </package> 

package com.almostman.action;

import org.apache.struts2.convention.annotation.Action;
import org.apache.struts2.convention.annotation.Namespace;
import org.apache.struts2.convention.annotation.ParentPackage;
import org.apache.struts2.convention.annotation.Result;

import com.opensymphony.xwork2.ActionSupport;

public class MainPageAction extends ActionSupport{

    /**
     * 
     */
    private static final long serialVersionUID = 1L;


    public String add() throws Exception {
        
        if("admin".equals(username) && "admin".equals(password)){
            return SUCCESS;
        }
        
        return INPUT;
    }
    
    private String username;
    private String password;
    
    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}