如何检测单个Action类中多个提交按钮场景中单击的提交按钮？

<s:form name="searchForm" action="employeeAction" method="post">
    <s:textfield name="id" label="Employee ID"/>
    <s:textfield name="name" label="Employee Name"/>

    <s:submit value="Search"/>
    <s:submit value="Add New"/>
</s:form>

在struts.xml中

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
    "http://struts.apache.org/dtds/struts-2.3.dtd">

<struts>

    <constant name="struts.enable.DynamicMethodInvocation" value="false" />
    <constant name="struts.devMode" value="true" />

    <package name="default" namespace="/" extends="struts-default">

        <default-action-ref name="index" />

        <global-results>
            <result name="error">/error.jsp</result>
        </global-results>

        <global-exception-mappings>
            <exception-mapping exception="java.lang.Exception" result="error"/>
        </global-exception-mappings>

    </package>

    <package name="example" namespace="/example" extends="default">

        <action name="employeeAction" class="example.EmployeeAction">
           <result name="search">/example/search.jsp</result>
           <result name="add" type="redirect">/example/add.jsp</result>
        </action>

    </package>
</struts>

在Struts Action类中,我们知道只有一个处理http请求的方法,即execute()方法.

在我预期的情况下,当我单击“搜索”按钮时,它将执行搜索数据并将数据呈现到/example/search.jsp,当我单击“添加新按钮”时,它将执行将页面重定向到/example/add.jsp.但是,单击时两个按钮都将进入execute()方法.所以我需要知道如何检测execute()方法中单击的按钮.

场景看起来像这样

public class EmployeeAction extends ActionSupport {

    public String execute() throws Exception {

        //PSEUDOCODE
        //IF (submitButton is searchButton) 
        //    return doSearch();
        //ELSE IF (submitButton is addNewButton) 
        //    return doAddNew();

        return SUCCESS;
    }

    public String doSearch() throws Exception {
        //perform search logic here
        return "search";
    }

    public String doAddNew() throws Exception {
        return "add";
    }
}