在重定向filter时停止进一步处理

我有URLRewirteFilter，它检查请求的域是否以www开头。 并重定向到no-www url。 当要重定向请求时，如何停止进一步处理（调用JSF应用程序，调用servlet等）？ 到目前为止我有这个：

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { HttpServletRequest req = (HttpServletRequest) request; String sn = req.getServerName().toLowerCase(); if (sn.startsWith("www.")) { String url = "http://" + getDefaultDomain() + req.getContextPath() + req.getRequestURI(); HttpServletResponse resp = (HttpServletResponse) response; resp.reset(); resp.setStatus(HttpServletResponse.SC_MOVED_PERMANENTLY); resp.setHeader("Location", url); } chain.doFilter(request, response); } 

Answer 1

只需在if的末尾添加一个return语句

 if (sn.startsWith("www.")) { String url = "http://" + getDefaultDomain() + req.getContextPath() + req.getRequestURI(); HttpServletResponse resp = (HttpServletResponse) response; resp.reset(); resp.setStatus(HttpServletResponse.SC_MOVED_PERMANENTLY); resp.setHeader("Location", url); return; } chain.doFilter(request, response); 

或者添加else

 if (sn.startsWith("www.")) { String url = "http://" + getDefaultDomain() + req.getContextPath() + req.getRequestURI(); HttpServletResponse resp = (HttpServletResponse) response; resp.reset(); resp.setStatus(HttpServletResponse.SC_MOVED_PERMANENTLY); resp.setHeader("Location", url); } else { chain.doFilter(request, response); } 

也可以看看：

• java.lang.IllegalStateException：提交响应后不能（转发| sendRedirect |创建会话）