不过,我想用GZIP压缩我的回应,可能的话.我尝试使用
Compression filter code可用于头部网站的免费下载.它适用于html,images,css和javascript.
我接下来张贴过滤器.它检查GZIP是否是接受的编码,并将gzip添加为Content-Encoding.请参阅:wrappedResp.setHeader(“Content-Encoding”,“gzip”);
public class CompressionFilter implements Filter { private ServletContext ctx; private FilterConfig cfg; /** * The init method saves the config object and a quick reference to the * servlet context object (for logging purposes). */ public void init(FilterConfig cfg) throws ServletException { this.cfg = cfg; ctx = cfg.getServletContext(); //ctx.log(cfg.getFilterName() + " initialized."); } /** * The heart of this filter wraps the response object with a Decorator * that wraps the output stream with a compression I/O stream. * Compression of the output stream is only performed if and only if * the client includes an Accept-Encoding header (specifically,for gzip). */ public void doFilter(ServletRequest req,ServletResponse resp,FilterChain fc) throws IOException,ServletException { HttpServletRequest request = (HttpServletRequest) req; HttpServletResponse response = (HttpServletResponse) resp; // Dose the client accept GZIP compression? String valid_encodings = request.getHeader("Accept-Encoding"); if ( (valid_encodings != null) && (valid_encodings.indexOf("gzip") > -1) ) { // Then wrap the response object with a compression wrapper // We'll look at this class in a minute. CompressionResponseWrapper wrappedResp = new CompressionResponseWrapper(response); // Declare that the response content is being GZIP encoded. wrappedResp.setHeader("Content-Encoding","gzip"); // Chain to the next component (thus processing the request) fc.doFilter(request,wrappedResp); // A GZIP compression stream must be "finished" which also // flushes the GZIP stream buffer which sends all of its // data to the original response stream. GZIPOutputStream gzos = wrappedResp.getGZIPOutputStream(); gzos.finish(); // The container handles the rest of the work. //ctx.log(cfg.getFilterName() + ": finished the request."); } else { fc.doFilter(request,response); //ctx.log(cfg.getFilterName() + ": no encoding performed."); } } public void destroy() { // nulling out my instance variables cfg = null; ctx = null; } }
我正在使用下一个代码在Struts Web应用程序中发送JSON响应.
public ActionForward get(ActionMapping mapping,ActionForm form,HttpServletRequest request,HttpServletResponse response) { JSONObject json = // Do some logic here RequestUtils.populateWithJSON(response,json); return null; } public static void populateWithJSON(HttpServletResponse response,JSONObject json) { if(json!=null) { response.setContentType("text/x-json;charset=UTF-8"); response.setHeader("Cache-Control","no-cache"); try { response.getWriter().write(json.toString()); } catch (IOException e) { throw new ApplicationException("IOException in populateWithJSON",e); } } }
它工作正常没有压缩,但如果我压缩JSON响应,我看不到我的JSON对象了.我使用JQuery处理JSON Ajax调用,代码片段如下:
$.post(url,parameters,function(json) { // Do some DOM manipulation with the data contained in the JSON Object },"json");
如果我看到响应与Firebug它是空的.
我应该折射我的压缩过滤器以在JSON响应中跳过压缩?还是有解决方法呢?
对我来说,看起来JQuery无法将响应识别为JSON,因为我正在添加Gzip压缩.
解决方法
If I see the response with Firebug it
is empty.
有你的线索 – 这不是一个JQuery问题,它是服务器端的. (恐怕我不能帮助你,除了建议你停止看客户端)
gzipping ajax响应没有问题 – 如果在Firebug中看不到响应,那么JQuery也看不到.