spring aop 拦截业务方法，实现权限控制示例
难点：aop类是普通的java类，session是无法注入的，那么在有状态的系统中如何获取用户相关信息呢，session是必经之路啊，获取session就变的很重要。思索很久没有办法，后来在网上看到了解决办法。
思路是：
i.SysContext 成员变量request,session,response
ii.Filter目的是给SysContext中的成员赋值
iii.然后在AOP中使用这个SysContext的值
要用好，需要理解 ThreadLocal和 和Filter执行顺序
1.aop获取request，response，session等
publicclassSysContext{
privatestaticThreadLocal<HttpServletRequest>requestLocal=newThreadLocal<HttpServletRequest>();
privatestaticThreadLocal<HttpServletResponse>responseLocal=newThreadLocal<HttpServletResponse>();
publicstaticHttpServletRequestgetRequest(){
returnrequestLocalget();
}
publicstaticvoidsetRequest(HttpServletRequestrequest){
requestLocalset(request);
}
publicstaticHttpServletResponsegetResponse(){
returnresponseLocalget();
}
publicstaticvoidsetResponse(HttpServletResponseresponse){
responseLocalset(response);
}
publicstaticHttpSessiongetSession(){
return(HttpSession)(getRequest())getSession();
}
}
2.添加过滤器
publicclassGetContextFilterimplementsFilter{
@Override
publicvoiddestroy(){
}
@Override
publicvoiddoFilter(ServletRequestrequest,ServletResponseresponse,
FilterChainchain)throwsIOException,ServletException{
SysContextsetRequest((HttpServletRequest)request);
SysContextsetResponse((HttpServletResponse)response);
chaindoFilter(request,response);
}
@Override
publicvoidinit(FilterConfigconfig)throwsServletException{
}
}
3.配置web.xml
将这部分放置在最前面，这样可以过滤到所有的请求
<filter> <filter-name>sessionFilter</filter-name> <filter-class>comuneifilterGetContextFilter</filter-class> </filter> <filter-mapping> <filter-name>sessionFilter</filter-name> <url-pattern>*</url-pattern> </filter-mapping>
4.springaopbefore
从session中取出用户名，如果不存在，抛出异常跳转，将错误信息放到request中
@Aspect
publicclassAdminAspect{
ActionContextcontext=ActionContextgetContext();
HttpServletRequestrequest;
HttpServletResponseresponse;
@Before("execution(*comuneiActionAdminActiongetPrivileges())")
publicvoidadminPrivilegeCheck()
throwsThrowable{
HttpSessionsession=SysContextgetSession();
request=SysContextgetRequest();
response=SysContextgetResponse();
StringuserName="";
try{
userName=sessiongetAttribute("userName")toString();
if(userName==null||userNameequals(""))
thrownewException("noprivilege");
}catch(Exceptionex){
requestsetAttribute("msg","{\"res\":\""+"无权限"+"\"}");
try{
requestgetRequestDispatcher("/jsp/jsonjsp")forward(
request,response);
}catch(ServletExceptione){
eprintStackTrace();
}catch(IOExceptione){
eprintStackTrace();
}
}
}
}
5.applicationContext.xml
<beanid="adminAspect"class="comuneiaopAdminAspect"></bean>
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持毛票票。