一、配置方法
1 映射過濾應用程序中所有資源
<filter> <filter-name>loggerfilter</filter-name> <filter-class>myfilter.LoggerFilter</filter-class></filter><filter-mapping> <filter-name>loggerfilter</filter-name> <url-pattern>/*</url-pattern> //訪問當前主機，當前應用程序根下的所有文件包括多級子目錄下的所有文件，注意這里*前有“/”</filter-mapping>
2 過濾指定的類型文件資源
<filter> <filter-name>loggerfilter</filter-name> <filter-class>myfilter.LoggerFilter</filter-class></filter><filter-mapping> <filter-name>loggerfilter</filter-name> <url-pattern>*.html</url-pattern> //訪問當前主機，當前應用程序根目錄下的所有html文件，注意：*.html前沒有“/”,否則錯誤</filter-mapping>
其中*.html要過濾jsp那么就改*.html為*.jsp，但是注意沒有“/”斜杠。如果要同時過濾多種類型資源：
方法1 url-pattern 分開寫
<filter> <filter-name>loggerfilter</filter-name> <filter-class>myfilter.LoggerFilter</filter-class></filter><filter-mapping> <filter-name>loggerfilter</filter-name> <url-pattern>*.html</url-pattern></filter-mapping><filter-mapping> <filter-name>loggerfilter</filter-name> <url-pattern>*.jsp</url-pattern>//訪問當前主機，當前應用程序根目錄以所有及子目錄下的所有jsp文件</filter-mapping>
方法2 將url-pattern合并
<filter> <filter-name>loggerfilter</filter-name> <filter-class>myfilter.LoggerFilter</filter-class></filter><filter-mapping> <filter-name>loggerfilter</filter-name> <url-pattern>*.html;*.jsp</url-pattern></filter-mapping>//*.html;*.jsp兩類型之間用分號;間隔
3 過濾指定的目錄下的所有文件
<filter> <filter-name>loggerfilter</filter-name> <filter-class>myfilter.LoggerFilter</filter-class></filter><filter-mapping> <filter-name>loggerfilter</filter-name> <url-pattern>/folder_name/*</url-pattern>//訪問當前主機，當前應用程序根目錄下的folder_name子目錄（可是多級子目錄）下所有文件</filter-mapping>
4 過濾指定的servlet
<filter> <filter-name>loggerfilter</filter-name> <filter-class>myfilter.LoggerFilter</filter-class></filter><filter-mapping> <filter-name>loggerfilter</filter-name> <servlet-name>loggerservlet</servlet-name></filter-mapping><servlet> <servlet-name>loggerservlet</servlet-name> <servlet-class>myfilter.LoggerServlet</servlet-class></servlet>
5 過濾指定文件（即單一文件）
<filter> <filter-name>loggerfilter</filter-name> <filter-class>myfilter.LoggerFilter</filter-class></filter><filter-mapping> <filter-name>loggerfilter</filter-name> <url-pattern>/simplefilter.html</url-pattern></filter-mapping>
6 過濾指定目錄下的指定類型的所有文件
這種情況下在web.xml中無法一次性配置完成，需要結合filter的實現類
首先在web.xml中配置過濾指定目錄下的所有文件
<filter> <filter-name>loggerfilter</filter-name> <filter-class>myfilter.LoggerFilter</filter-class></filter><filter-mapping> <filter-name>loggerfilter</filter-name> <url-pattern>/dir_name/*</url-pattern></filter-mapping>
然后在filter的實現類中的doFilter方法中獲取請求的uri或者url，判斷uri或者url中是否包含指定文件類型的字符串，決定是否過濾
//獲得用戶請求的uriString uri = request.getRequestURI();if(uri.contains(".jsp")||uri.contains(".html"))System.out.println("開始過濾"+url);7 過濾指定目錄下指定類型的單一文件
<filter> <filter-name>loggerfilter</filter-name> <filter-class>myfilter.LoggerFilter</filter-class></filter><filter-mapping> <filter-name>loggerfilter</filter-name> <url-pattern>/dir_name/index.jsp</url-pattern></filter-mapping>
以上都要注意是否有斜杠“/”
二、實例
不緩存文件
<filter> <filter-name>NoCache</filter-name> <filter-class>com.sys.common.Filters.ResponseHeaderFilter </filter-class> <init-param> <param-name>Cache-Control</param-name> <param-value>no-cache, must-revalidate</param-value> </init-param> </filter>
緩存文件一周
<filter> <filter-name>CacheForWeek</filter-name> <filter-class>com.sys.common.Filters.ResponseHeaderFilter </filter-class> <init-param> <param-name>Cache-Control</param-name> <param-value>max-age=604800, public</param-value> </init-param> </filter><filter-mapping> <filter-name>CacheForWeek</filter-name> <url-pattern>/images/*</url-pattern> </filter-mapping> <filter-mapping> <filter-name>CacheForWeek</filter-name> <url-pattern>*.js</url-pattern> </filter-mapping> <filter-mapping> <filter-name>CacheForWeek</filter-name> <url-pattern>*.css</url-pattern> </filter-mapping>
自定義的filter：
public class ResponseHeaderFilter implements Filter { FilterConfig fc; public void doFilter(ServletRequest req, ServletResponse res,FilterChain chain) throws IOException, ServletException { HttpServletResponse response = (HttpServletResponse) res; for (Enumeration e = fc.getInitParameterNames(); e.hasMoreElements();) { String headerName = (String) e.nextElement(); response.addHeader(headerName, fc.getInitParameter(headerName)); } chain.doFilter(req, response); } public void init(FilterConfig filterConfig) { this.fc = filterConfig; } public void destroy() { this.fc = null; }}以上這篇JSP過濾器Filter配置過濾類型全部匯總就是小編分享給大家的全部內容了，希望能給大家一個參考，也希望大家多多支持武林網。
新聞熱點
疑難解答
