- 问题原因: 如果重定向了就不能让filterChain.doFilter(req, resp)继续执行,否则还是会走下去。
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException { HttpServletRequest req = (HttpServletRequest) servletRequest; HttpServletResponse resp = (HttpServletResponse) servletResponse; if (req.getSession().getAttribute(Constants.USER_SESSION) == null) { resp.sendRedirect(req.getContextPath() + "/error.jsp"); } else{ filterChain.doFilter(req, resp); } }