Web 專案工程中獲取全域性Request物件
阿新 • • 發佈：2019-01-29
日常開發過程中有很多資訊是存在於Session物件中的，而session物件的獲取需要request物件，但是在沒有請求的普通類中如何獲取request則成了很多問題的根源，我們通常的解決辦法是使用過濾器Filter通過Filter可以實現request物件全域性化。
package org.dbzy.analyse.utils; 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; public class RequestFilter implements Filter { public static ThreadLocal<HttpServletRequest> threadLocalRequest = new ThreadLocal<HttpServletRequest>(); public static ThreadLocal<HttpServletResponse> threadLocalResponse = new ThreadLocal<HttpServletResponse>(); public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2) throws IOException, ServletException { threadLocalRequest.set((HttpServletRequest) arg0); threadLocalResponse.set((HttpServletResponse) arg1); arg2.doFilter(arg0, arg1); } public void destroy() { } public void init(FilterConfig arg0) throws ServletException { } }
在程式碼中通過RequestFilter.threadLocalRequest.get()，即可取得對應的request物件。
同時在web.xml中配置Filter。
<filter> <filter-name>RequestFilter</filter-name> <filter-class>Filter類全路徑</filter-class> </filter> <filter-mapping> <filter-name>RequestFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping>