code: @Override
      public void checkVaild() {
          super.checkVaild();
          if (this.paymoney < 1) throw new RuntimeException("paymoney is illegal");
          if (this.paytitle == null || this.paytitle.isEmpty()) throw new RuntimeException("paytitle is illegal");
          if (this.paybody == null || this.paybody.isEmpty()) throw new RuntimeException("paybody is illegal");
          if (this.clientAddr == null || this.clientAddr.isEmpty()) throw new RuntimeException("clientAddr is illegal");
          if (this.paytimeout < 300) throw new RuntimeException("paytimeout cannot less 300 seconds");
          if (this.paytimeout > 24 * 60 * 60) throw new RuntimeException("paytimeout cannot greater 1 day");
      }
docs: 扩展信息