(转)Spring AOP 取得 web 的 request response 和 session

文章来源：http://blog.csdn.net/kvgnt/archive/2011/02/21/6198750.aspx

 

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 session =  (Map)ActionContext.getContext().getSession();
HttpServletRequest request = (HttpServletRequest) ActionContext.getContext().get(ServletActionContext.HTTP_REQUEST);
HttpServletResponse response = (HttpServletResponse) ActionContext.getContext().get(ServletActionContext.HTTP_RESPONSE);

 或直接用
HttpServletRequest request = ServletActionContext.getRequest();

 

---

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 requestLocal= new ThreadLocal();
     private static ThreadLocal responseLocal= new ThreadLocal();

    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 {
    @Override
    public void destroy() {
        // TODO Auto-generated method stub
    }
    @Override
    public void doFilter(ServletRequest arg0, ServletResponse arg1,
            FilterChain arg2) throws IOException, ServletException {
        SysContent.setRequest((HttpServletRequest) arg0);
        SysContent.setResponse((HttpServletResponse) arg1);
        arg2.doFilter(arg0, arg1);
    }
    @Override
    public 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

 

view plain copy to clipboard print ?

<filter>
         <filter-name>GetContentfilter-name>
         <filter-class>com.exdoit.aop.GetContentfilter-class>
    filter>
    <filter-mapping>
        <filter-name>GetContentfilter-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