public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest) request;
HttpServletResponse resp = (HttpServletResponse) response;
第一行resp.setHeader("Cache-Control","no-cache");
第二行resp.setHeader("Cache-Control","no-store");
第三行resp.setDateHeader("Expires",0);
第四行resp.setHeader("Pragma","no-cache");
第五行HttpSession session = req.getSession();
第六行Radmanage manager = (Radmanage)session.getAttribute("manager");
if(manager == null || manager.equals("")){
resp.sendRedirect("error.jsp?id=2&meta=3");
}
else{
chain.doFilter(req,resp);
}
}帮我解释一下他们的用途谢谢各位高手!!!
FilterChain chain) throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest) request;
HttpServletResponse resp = (HttpServletResponse) response;
第一行resp.setHeader("Cache-Control","no-cache");
第二行resp.setHeader("Cache-Control","no-store");
第三行resp.setDateHeader("Expires",0);
第四行resp.setHeader("Pragma","no-cache");
第五行HttpSession session = req.getSession();
第六行Radmanage manager = (Radmanage)session.getAttribute("manager");
if(manager == null || manager.equals("")){
resp.sendRedirect("error.jsp?id=2&meta=3");
}
else{
chain.doFilter(req,resp);
}
}帮我解释一下他们的用途谢谢各位高手!!!
第二行resp.setHeader("Cache-Control","no-store");
第三行resp.setDateHeader("Expires",0);
第四行resp.setHeader("Pragma","no-cache");
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
清ie缓存
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
第五行HttpSession session = req.getSession();
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
得到session
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
第六行Radmanage manager = (Radmanage)session.getAttribute("manager");
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~`
得到session里面的一个对象,如果存在chain.doFilter(req,resp);
不存在跳error page
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~