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public class LoginFilter implements Filter{
@Override
public void destroy() {
// TODO Auto-generated method stub
}
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
System.out.println("lanjieqi");
//获取HttpSession对象,判断是否登陆
HttpServletRequest req = (HttpServletRequest) request;
HttpServletResponse res = (HttpServletResponse) response;
HttpSession session = req.getSession();
if(session.getAttribute("user")==null){
res.sendRedirect(req.getContextPath() + "/linli1/index.jsp");
}else{
chain.doFilter(request, response);
}
}
@Override
public void init(FilterConfig arg0) throws ServletException {
}