private String buildEmailBody(Bill bill) {
   StringBuffer sb = new StringBuffer();
   sb.append(
       "您有一条新任务,请进入<a href=\""
           + WebConstants.URL
           + "\" target=\"_blank\">"
           + WebConstants.URL
           + "</a>来处理");
   sb.append("农场管区: ");
   sb.append(bill.getFarm() == null ? "" : bill.getFarm().getName());
   sb.append("-" + bill.getArea() == null ? "" : bill.getArea().getName());
   sb.append("\n");
   sb.append("饲料经理签名:" + (bill.getManager() == null ? "" : bill.getManager().getName()));
   sb.append("\n");
   sb.append("单据编号:" + bill.getOrderId());
   sb.append("\n");
   sb.append("管区:" + (bill.getArea() == null ? "" : bill.getArea().getName()));
   sb.append("\n");
   sb.append("单据:" + (bill.getOrderNo() == null ? "" : bill.getOrderNo()));
   sb.append("\n");
   sb.append("负责人:" + bill.getCurrUserName());
   sb.append("\n");
   sb.append("饲料规格:" + bill.getModel());
   sb.append("\n");
   sb.append("饲料型号:" + bill.getSize());
   sb.append("\n");
   sb.append("饲料吨数:" + bill.getAmount());
   sb.append("\n");
   sb.append("预计达到时间:" + Util.getDate(bill.getPlanDate()));
   sb.append("\n");
   return sb.toString();
 }