//start html email 将HMTL文件写入邮件流里面
                  InputStream is = file.getContent().getInputStream();
                  if(is!=null && file.getName().getExtension().equals("html")){
//                  System.out.println(file.getName().getExtension()); 

                  //set html  to a string
                      MimeBodyPart htmlContent = new MimeBodyPart();
                      byte[] bytes = new byte[1024];
                      String html = "";
                      int c;
                      while((c=is.read(bytes))!=-1){
                      html = html + new String(bytes,0,c);
                      }
//                    System.out.println(html); 

  //replace the image url with new cid url
                      String IMG_REGEX = "<\s*img\s+(?:[^\s>]\s*){0,}src\s*=\s*["']\s*([^"'\s>]*)\s*["'](?:\s*[^\s>]){0,}\s*>";
                      String PREFIX_IMG = "img_";
              Map urlMap = new HashMap();
              Pattern p = Pattern.compile(IMG_REGEX);
              Matcher m = p.matcher(html);
              String url = null;
              String cid = null;
              int i = 1;
              // replace image url
              while (m.find()) {
            url = m.group(1);
            if (StringUtils.hasText(url)) {
            if (!urlMap.containsKey(url)) {
            cid = PREFIX_IMG+(i++);
            urlMap.put(url, cid);
              html = html.replaceAll(url, "cid:"+cid);
            }
            }
               }
            //add html into email
            htmlContent.setContent(html, "text/html; " + "charset=utf-8");
                     parts.addBodyPart(htmlContent); 

            //add html's image  into email
            Iterator urlIterator = urlMap.keySet().iterator();
            while (urlIterator.hasNext()) {
            url = urlIterator.next();
            cid = urlMap.get(url); 

            MimeBodyPart imageFile = new MimeBodyPart(); 

            byte [] imageBytes = file2byte(url);
            DataHandler dh = new DataHandler(new ByteArrayDataSource((byte[])imageBytes,"application/octet-stream")); 

          imageFile.setDataHandler(dh);
            imageFile.setFileName(cid);
//             imageFile.setHeader("Content-ID", "IMG" + new Integer(i).toString());
            parts.addBodyPart(imageFile); 

//             System.out.println(html);
//             System.out.println(cid);
              } 

                  }
                  //end html email