spring拦截器的简单实现Interceptor

时间:2022-03-29 06:18:34

原文链接:http://lixuanbin.iteye.com/blog/2250100

1. 需求描述

某内部管理系统采用Spring MVC搭建,用户可以登录系统进行CRUD以及其他的一些日常管理操作。现在希望对某些敏感操作(譬如修改重要数据)进行拦截,在日志中记录下该操作的执行人,操作时间,操作名称,传入参数以及返回结果等信息,以便万一出问题后追究查验。

2. 解决思路

有两种方案:

(1)把对应的MVC方法使用AOP去拦截,这个是方法级别的拦截;

(2)使用Spring MVC Interceptor去拦截,这个是基于URL的拦截。

那么,如何选择呢?考虑到我们这个是WEB项目,只有登录用户才能执行管理操作,而登录用户的用户信息一般放在Session里,使用基于URL拦截的方法便于提取Session数据;而且,被Spring MVC @Controller注解的类,都被AnnotationMethodHandlerAdapter给代理了,使用AOP进行拦截的话需要做些特殊处理。所以,在这里我们选择使用Interceptor拦截。

3. 具体实现

(1)Spring配置文件

在beans头部标签加入:

...

xmlns:mvc="http://www.springframework.org/schema/mvc"

...

xsi:schemaLocation="...

http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd

..."

然后加上mvc:interceptors拦截声明:

 <mvc:interceptors>
<mvc:interceptor>
<mvc:mapping path="/**"/><!--拦截所有controller-->
<mvc:exclude-mapping path="/js/**" />
<mvc:exclude-mapping path="/css/**" />
<mvc:exclude-mapping path="/img/**" />
<mvc:exclude-mapping path="*.woff" />
<mvc:exclude-mapping path="*.ico" />
<mvc:exclude-mapping path="*.swf" />
<mvc:exclude-mapping path="*.png" />
<bean id="log4UpdateOrDeleteInterceptor"
class="com.XXX.testmvc.interceptor.Log4UpdateOrDeleteInterceptor"></bean>
</mvc:interceptor>
</mvc:interceptors>
    Spring的拦截路径采用了AntPathMatcher的方式。以下是引用自官方的说明:

The mapping matches URLs using the following rules:

  • ? matches one character
  • * matches zero or more characters
  • ** matches zero or more 'directories' in a path

Some examples:

  • com/t?st.jsp - matches com/test.jsp but also com/tast.jsp or com/txst.jsp
  • com/*.jsp - matches all .jsp files in the com directory
  • com/**/test.jsp - matches all test.jsp files underneath the com path
  • org/springframework/**/*.jsp - matches all .jsp files underneath the org/springframework path
  • org/**/servlet/bla.jsp - matches org/springframework/servlet/bla.jsp but also org/springframework/testing/servlet/bla.jsp and org/servlet/bla.jsp

(2)实现拦截器

继承HandlerInterceptorAdapter并按需覆写里面的preHandle和postHandle方法即可。

 /**
* 拦截敏感操作并记录到日志
*
* @author */
public class Log4UpdateOrDeleteInterceptor extends HandlerInterceptorAdapter {
protected static final Logger log = Logger.getLogger(Log4UpdateOrDeleteInterceptor.class); public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
Object handler) throws Exception {
HttpSession session = request.getSession();
String requestUri = request.getRequestURI();
log.debug("request uri:" + requestUri);
String contextPath = request.getContextPath();
String url = requestUri.substring(contextPath.length());
if (StringUtils.contains(url, "add") || StringUtils.contains(url, "edit")
|| StringUtils.contains(url, "delete")) {
String user = session.getAttribute(SessionKey.USERNAME_SESSION_NAME) != null ? (String) session
.getAttribute(SessionKey.USERNAME_SESSION_NAME) : null;
StringBuffer sb = new StringBuffer();
Enumeration<String> a = null;
a = request.getParameterNames();
while (a.hasMoreElements()) {
String key = a.nextElement();
sb.append(key + ":" + request.getParameter(key) + ", ");
}
log.warn(String.format("FBI request warning! user: %s, url: %s, params: {%s}", user,
url, StringUtils.removeEnd(StringUtils.trim(sb.toString()), ",")));
}
return true;
} public void postHandle(HttpServletRequest request, HttpServletResponse response, Object o,
ModelAndView mav) throws Exception {
HttpSession session = request.getSession();
String requestUri = request.getRequestURI();
log.debug("request uri:" + requestUri);
String contextPath = request.getContextPath();
String url = requestUri.substring(contextPath.length());
if ((StringUtils.contains(url, "add") || StringUtils.contains(url, "edit") || StringUtils
.contains(url, "delete")) && mav != null) {
String user = session.getAttribute(SessionKey.USERNAME_SESSION_NAME) != null ? (String) session
.getAttribute(SessionKey.USERNAME_SESSION_NAME) : null;
Map<String, Object> map = mav.getModel();
StringBuffer sb = new StringBuffer();
for (Map.Entry<String, Object> entry : map.entrySet()) {
sb.append(entry.getKey() + ":"
+ (entry.getValue() != null ? entry.getValue().toString() : null) + ", ");
}
log.warn(String.format("FBI response warning! user: %s, url: %s, models: {%s}", user,
url, StringUtils.removeEnd(StringUtils.trim(sb.toString()), ",")));
}
} public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object o,
Exception excptn) throws Exception {
// System.out.println("afterCompletion");
} }

本例检查URI是否含有敏感操作来判断是否需要进行日志记录,如果您采用了REST接口,也可以加上request method的校验。