struts2.x依赖注入无效的问题

package com.loginCheck;



import com.opensymphony.xwork2.ActionSupport;



public class LoginAction extends ActionSupport {

	private String userName=null;

	private String userPassword=null;

	

	

	@Override

	public String execute(){

		if(userName != null) {

			if(userName.equals("wuyanxue")) {

				

				return SUCCESS;	

			}

		}

		System.out.println(userName+" "+userPassword);

		return ERROR;

	}



	public void setUserName(String userName) {

		this.userName = userName;

	}



	public String getUserName() {

		return userName;

	}



	public void setUserPassword(String userPassword) {

		this.userPassword = userPassword;

	}



	public String getUserPassword() {

		return userPassword;

	}



}

这是Action类

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这是jsp页面的表单

<s:form action="login?request_locale=en_US" method="get">
      <s:textfield name="userName" key="loginUserName" ></s:textfield>
      <s:password name="userPassword" key="loginUserPassword" ></s:password>
      <s:submit key="submit"></s:submit>
     </s:form>

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这是struts.xml的配置

<struts>

	 

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

	<constant name="struts.custom.i18n.resources" value="myResources"></constant>

	

	

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

		<global-exception-mappings>

			<exception-mapping result="Exception" exception="java.lang.Exception">

			</exception-mapping>

		</global-exception-mappings>

		<action name="login" class="com.loginCheck.LoginAction">

            <interceptor-ref name="logger" />

            <interceptor-ref name="timer" />

        	<exception-mapping result="SQLException" exception="java.sql.SQLException"></exception-mapping>

            <result name="success">

            	/loginSuccess.jsp

            </result>

            <result name="error">

            	/loginFail.jsp

            </result>

        </action>

	

    </package>



</struts>

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