java – 使用GZIP,JSON响应和JQuery

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.