先看下文件的目录结构:
我们要做的就是用MyFirstFilter过滤servlet包内的所有servlet即DisplayHeader、HelloServlet、SecondServlet。 主要就是两个注意事项: 1:
package servlet; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** * Servlet implementation class HelloServlet */ @WebServlet("/servlet/HelloServlet") public class HelloServlet extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public HelloServlet() { super(); // TODO Auto-generated constructor stub } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub // String msg = request.getInputStream().toString(); // response.getWriter().println("��������"); response.getWriter().println(request.getAttribute("ServletPath")); response.getWriter().println("公司的分公司"); // request.setAttribute("name", "��������HelloServlet����Ϣmarhong"); // request.getRequestDispatcher("/SecondServlet").forward(request, response); } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub doGet(request, response); } }这里一定要注意就是那个注释部分:
它原来的值是:@WebServlet(“/HelloServlet”),一定要改成上图所示的才可以
2.就是web.xml了,代码如下所示:
<?xml version="1.0" encoding="UTF-8"?> <web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <filter> <filter-name>MyFirstFilter</filter-name> <filter-class>com.util.MyFirstFilter</filter-class> <init-param> <param-name>encoding</param-name> <param-value>GBK</param-value> </init-param> <init-param> <param-name>secondAttribute</param-name> <param-value>filterConfig的第二个参数</param-value> </init-param> </filter> <filter-mapping> <filter-name>MyFirstFilter</filter-name> <url-pattern>/servlet/*</url-pattern> <url-pattern>/checkIn.jsp</url-pattern> </filter-mapping> <servlet> <!-- 类名 --> <servlet-name>HelloServlet</servlet-name> <!-- 所在的包 --> <servlet-class>servlet.HelloServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>HelloServlet</servlet-name> <!-- 访问的网址 --> <url-pattern>/SummerTest/servlet/HelloServlet</url-pattern> </servlet-mapping> <servlet> <servlet-name>SecondServlet</servlet-name> <servlet-class>servlet.SecondServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>SecondServlet</servlet-name> <!-- 访问的网址 --> <url-pattern>/SummerTest/servlet/SecondServlet</url-pattern> </servlet-mapping> <servlet> <!-- 类名 --> <servlet-name>DisplayHeader</servlet-name> <!-- 所在的包 --> <servlet-class>servlet.DisplayHeader</servlet-class> </servlet> <servlet-mapping> <servlet-name>DisplayHeader</servlet-name> <!-- 访问的网址 --> <url-pattern>/SummerTest/servlet/DisplayHeader</url-pattern> </servlet-mapping> </web-app>注意这两个地方应该就可以达到目的了。
