<filter> <filter-name>UsersFilter</filter-name> <filter-class>com.web.UsersFilter</filter-class> </filter> <filter-mapping> <filter-name>UsersFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping>
package com.web;
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 javax.servlet.http.HttpSession;
public class UsersFilter implements Filter {
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
// 設置請求的字符編碼
request.setCharacterEncoding("UTF-8");
// 設置返回請求的字符編碼
response.setCharacterEncoding("UTF-8");
// 轉換ServletRequest為 HttpServletRequest
HttpServletRequest req = (HttpServletRequest) request;
// 轉換ServletResponse為HttpServletRequest
HttpServletResponse res = (HttpServletResponse) response;
// 獲取Session
HttpSession session = req.getSession();
// 獲取Session中存儲的對象
Object o = session.getAttribute("user");
// 獲取當前請求的URI
String url = req.getRequestURI();
// 判斷Session中的對象是否為空；判斷請求的URI是否為不允許過濾的URI
if (o==null && url.indexOf("test.jsp")<0
&& url.indexOf("comment.jsp")<0
&& url.indexOf("link.jsp")<0) {
chain.doFilter(request, response);
res.setHeader("Cache-Control","no-store");
res.setDateHeader("Expires",0);
res.setHeader("Pragma","no-cache");
res.flushBuffer();
}
}
public void destroy() {
// TODO Auto-generated method stub
}
public void init(FilterConfig arg0) throws ServletException {
// TODO Auto-generated method stub
}
}
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