java微信退款的代码片段 支持部分退款

import java.math.BigDecimal;
import com.alibaba.fastjson.JSON;
import com.github.binarywang.wxpay.bean.request.WxPayRefundRequest;
import com.github.binarywang.wxpay.bean.result.WxPayRefundResult;
import com.github.binarywang.wxpay.config.WxPayConfig;
import com.github.binarywang.wxpay.exception.WxPayException;
import com.github.binarywang.wxpay.service.WxPayService;
import com.github.binarywang.wxpay.service.impl.WxPayServiceImpl;

public class WeixinRefund {

public static int refund() {

WxPayConfig payConfig = new WxPayConfig();
payConfig.setAppId("微信APPID");
    payConfig.setMchId("微信商户号");
    payConfig.setMchKey("微信支付KEY");
    payConfig.setKeyPath("微信支付秘钥路径");
WxPayService wxPayService = new WxPayServiceImpl();
wxPayService.setConfig(payConfig);

WxPayRefundRequest request = new WxPayRefundRequest();
request.setOutRefundNo("随机退款单号");
request.setOutTradeNo("商户订单号");
request.setRefundFee(退款金额); // 注意！以分为单位
request.setRefundDesc("退款备注");
request.setTotalFee(订单总金额); // 注意！以分为单位

try {
WxPayRefundResult result = wxPayService.refund(request);