public?class?LoginAction?extends?ActionSupport?implements?SessionAware{
private?String?username;
private?String?password;
?private?Map<String,Object>?session;
?/*
??*?該方法是獲取session對象
??*?(non-Javadoc)
??*?@see?org.apache.struts2.interceptor.SessionAware#setSession(java.util.Map)
??*/
@Override
public?void?setSession(Map<String,?Object>?session)?{
//?TODO?Auto-generated?method?stub
this.session=session;
}
?????????public?String?login(){
???????????if("admin".equals(username)?&&?"123".equals(password)){
???????????	session.put("username",username);
???????????	return?SUCCESS;
???????????}
???????????else{
???????????	session.put("usernameerror","用戶名輸入不正確");
???????????	return?ERROR;
???????????}
?????????}
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;
}

?????????
}

<?xml?version="1.0"?encoding="UTF-8"??>
<!DOCTYPE?struts?PUBLIC?"-//Apache?Software?Foundation//DTD?Struts?Configuration?2.1//EN"?"http://struts.apache.org/dtds/struts-2.1.dtd">
<struts>
????<package?name="default"?namespace="/"?extends="struts-default">
????<interceptors>
????<interceptor?name="LoginInteceptor"?class="com.inteceptor.LoginInteceptor"></interceptor>
????</interceptors>
????<action?name="auth">
<result>/WEB-INF/page/user.jsp</result>
<result?name="login">/index.jsp</result>
<!--?引用自定義的攔截器?-->
<interceptor-ref?name="LoginInteceptor"></interceptor-ref>

</action>

??????<action?name="LoginAction"?method="login"?class="com.action.LoginAction">
??????
??????<result>/WEB-INF/source/user.jsp</result>
??????<result?name="ERROR">/index2.jsp</result>
??????
??????</action>
????</package>
</struts>

public?class?LoginInteceptor?extends?AbstractInterceptor?{

	

	@Override
	public?String?intercept(ActionInvocation?invocation)?throws?Exception?{
		//獲取用戶上下文
		ActionContext?context=ActionContext.getContext();
		Map<String,Object>?session=context.getSession();
		if(session.get("username")!=null){
			String?result=invocation.invoke();
			System.out.println(result);
			return?result;
		}
		else{
			return?"login";
		}
		
	}

}

<h2>用戶登錄</h2>
???${usernameerror}
????<form?action="LoginAction.action"?method="post">
?????用戶名：?<input?type="text"?name="username"?value=""/>
?????密碼：??<input?type="password"?name="password"?value="">
?????<input?type="submit"?value="登錄"/>
????</form>