spring AOP 取得 web 的 request response 和 session

struts2里关于 Spring Aop 切面方法里直接使用 com.opensymphony.xwork2.ActionContext 就可以得到了.初学绕了一个大弯..唉.

当然,action里也可以这么拿.不过action里更建议实现 SessionAware, ServletRequestAware, ServletResponseAware 这3个接口来获得.假如使用的是实现接口的方式,不要在构造函数里使用这3个对象,因为action对象构建时这3个对象还不一定获取到,可能空指针.

Map<String,Object> session =  (Map<String,Object>)ActionContext.getContext().getSession();HttpServletRequest request = (HttpServletRequest) ActionContext.getContext().get(ServletActionContext.HTTP_REQUEST);HttpServletResponse response = (HttpServletResponse) ActionContext.getContext().get(ServletActionContext.HTTP_RESPONSE);

String path = request.getRealPath("/");

Java显示已过时，替代方法为 request.getSession().getServletContext().getRealPath("/");

注： request.getRealPath("")

就是取得你当前运行文件在服务器上的绝对路径.

request.getRealPath("/")

取得当前站点的根目录.

下面这个过时了..貌似 struts1 里是这么干的.

建立一个类,里面的2个静态变量ThreadLocal用来保存当前线程的request和response

package com.exdoit.tool;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;public class SysContent { private static ThreadLocal<HttpServletRequest> requestLocal= new ThreadLocal<HttpServletRequest>(); private static ThreadLocal<HttpServletResponse> responseLocal= new ThreadLocal<HttpServletResponse>(); public static HttpServletRequest getRequest() {return (HttpServletRequest)requestLocal.get();}public static void setRequest(HttpServletRequest request) {requestLocal.set(request);}public static HttpServletResponse getResponse() {return (HttpServletResponse)responseLocal.get();}public static void setResponse(HttpServletResponse response) {responseLocal.set(response);}public static HttpSession getSession() {return (HttpSession)((HttpServletRequest)requestLocal.get()).getSession();}}

创建一个过滤器.把当前线程的request和response赋到之前类的静态变量里

package com.exdoit.aop;import java.io.IOException;import javax.servlet.Filter;import javax.servlet.FilterChain;import javax.servlet.FilterConfig;import javax.servlet.ServletException;import javax.servlet.ServletRequest;import javax.servlet.ServletResponse;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.exdoit.tool.SysContent;public class GetContent implements Filter {@Overridepublic void destroy() {// TODO Auto-generated method stub}@Overridepublic void doFilter(ServletRequest arg0, ServletResponse arg1,FilterChain arg2) throws IOException, ServletException {SysContent.setRequest((HttpServletRequest) arg0);SysContent.setResponse((HttpServletResponse) arg1);arg2.doFilter(arg0, arg1);}@Overridepublic void init(FilterConfig arg0) throws ServletException {// TODO Auto-generated method stub}}

配置WEB.XML,加载过滤器我把这段节点放到了web.xml的最前面.保证一开始就得到变量

<filter>     <filter-name>GetContent</filter-name>     <filter-class>com.exdoit.aop.GetContent</filter-class></filter><filter-mapping>        <filter-name>GetContent</filter-name>        <url-pattern>/*</url-pattern>    </filter-mapping>

拦截器里的执行方法

public void rightFilter(JoinPoint joinPoint) throws Exception {HttpServletRequest request = SysContent.getRequest();HttpServletResponse response = SysContent.getResponse();HttpSession session = SysContent.getSession();//其他操作}

之后在其他拦截器或action...等对象中,要使用这3个变量.都可以直接通过SysContent.getXX() 得到

参考 http://www.javaeye.com/topic/103804 正确理解ThreadLocal http://www.javaeye.com/topic/617368 关于ThreadLocal模式的体会