Java - 微信支付

首先贴出官方文档，关于介绍，场景，参数说明，可以直接看文档：https://pay.weixin.qq.com/wiki/doc/api/index.html

一. APP支付

官方文档：https://pay.weixin.qq.com/wiki/doc/api/app/app.php?chapter=9_1

推荐maven依赖：

<!--微信支付sdk -->
<dependency><groupId>com.github.wxpay</groupId><artifactId>wxpay-sdk</artifactId><version>3.0.9</version>
</dependency>

1. 【统一下单】

商户系统先调用该接口在微信支付服务后台生成预支付交易单，返回正确的预支付交易会话标识后再在APP里面调起支付。

微信统一工具类

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.lang.reflect.Field;
import java.security.KeyStore;
import java.security.SecureRandom;
import java.util.*;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.github.wxpay.sdk.WXPayConstants;
import com.github.wxpay.sdk.WXPayUtil;
import com.google.common.collect.Maps;
import org.apache.commons.lang.StringUtils;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.conn.ssl.DefaultHostnameVerifier;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.BasicHttpClientConnectionManager;
import org.apache.http.util.EntityUtils;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.web.client.RestTemplate;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.crypto.Cipher;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.SecretKeySpec;
import java.security.InvalidKeyException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.Security;public class WXUtil {public static final String APP_ID = "";public static final String APPLET_APP_ID = "";public static final String MCH_ID = ""; // 微信商户号public static final String KEY = "";  // 微信支付密钥public static final String NOTIFY_URL = ""; // 微信支付成功回调urlpublic static final String REFUND_NOTIFY_URL = "";   // 微信退款成功回调public static final String SIGN_PACKAGE = "Sign=WXPay";private static Cipher cipher = null;  //解码器public static String createSign(Map parameters) throws Exception {List<String> keys = new ArrayList<String>(parameters.keySet());Collections.sort(keys);String prestr = "";for (int i = 0; i < keys.size(); i++) {String key = keys.get(i);Object value = parameters.get(key);
//        value = URLEncoder.encode(value, "UTF-8");if(StringUtils.isNotBlank(parameters.get(key)+"") && value != null) {if (i == keys.size() - 1) {//拼接时，不包括最后一个&字符prestr = prestr + key + "=" + value;} else {prestr = prestr + key + "=" + value + "&";}	}}prestr += "&key="+KEY;return prestr;}public static Map<String, Object> objectToMap(Object obj) throws Exception { if(obj == null){ return null; } Map<String, Object> map = new HashMap<String, Object>(); Field[] declaredFields = obj.getClass().getDeclaredFields(); for (Field field : declaredFields) { field.setAccessible(true); map.put(field.getName(), field.get(obj)); } return map; }public static Map applayRefund(String userId, String payId, String orderNo, Double amount, Double refundMoney) throws Exception {Map map = new HashMap();map.put("appid", APP_ID);map.put("mch_id", MCH_ID);map.put("nonce_str", UUID_MD5.getUUID());map.put("transaction_id", payId);map.put("out_refund_no", orderNo);int total_fee = (int) (amount * 100);map.put("total_fee", total_fee+"");int refund_fee = (int) (refundMoney * 100);map.put("refund_fee", refund_fee+"");map.put("notify_url", REFUND_NOTIFY_URL);String stringSign = WXUtil.createSign(map);String sign = WXPayUtil.MD5(stringSign).toUpperCase();map.put("sign", sign);String data = WXPayUtil.mapToXml(map);File file = new File("apiclient_cert.p12");InputStream in = new FileInputStream(file);char password[] = WXUtil.MCH_ID.toCharArray();java.io.InputStream certStream = in;KeyStore ks = KeyStore.getInstance("PKCS12");ks.load(certStream, password);KeyManagerFactory kmf = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());kmf.init(ks, password);SSLContext sslContext = SSLContext.getInstance("TLS");sslContext.init(kmf.getKeyManagers(), null, new SecureRandom());SSLConnectionSocketFactory sslConnectionSocketFactory = new SSLConnectionSocketFactory(sslContext,new String[] { "TLSv1" }, null, new DefaultHostnameVerifier());BasicHttpClientConnectionManager connManager = new BasicHttpClientConnectionManager();CloseableHttpClient httpClient = HttpClients.custom().setSSLSocketFactory(sslConnectionSocketFactory).build();String url = (new StringBuilder()).append("https://").append("api.mch.weixin.qq.com").append("/secapi/pay/refund").toString();HttpPost httpPost = new HttpPost(url);RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(10000).setConnectTimeout(10000).build();httpPost.setConfig(requestConfig);StringEntity postEntity = new StringEntity(data, "UTF-8");httpPost.addHeader("Content-Type", "text/xml");httpPost.addHeader("User-Agent", (new StringBuilder()).append(WXPayConstants.USER_AGENT).append(" ").append(map.get("mch_id")).toString());httpPost.setEntity(postEntity);CloseableHttpResponse httpResponse = httpClient.execute(httpPost);org.apache.http.HttpEntity httpEntity = httpResponse.getEntity();String reponseString = EntityUtils.toString(httpEntity, "UTF-8");return WXPayUtil.xmlToMap(reponseString);}/*** 提现* @param openid 微信openid* @param realName 真实姓名* @param money 提现金额* @return* @throws Exception*/public static Map wxWithdraw(String openid,String realName, Double money) throws Exception{Map map = new HashMap();map.put("mch_appid", APP_ID);map.put("mchid", MCH_ID);map.put("nonce_str", UUID_MD5.getUUID());map.put("partner_trade_no", UUID_MD5.getUUID());map.put("openid", openid);map.put("check_name", "FORCE_CHECK"); //强制实名，如需不校真实姓名，则改为NO_CHECKmap.put("re_user_name", realName);int total_fee = (int) (money * 100);map.put("amount", total_fee+"");map.put("desc", "账户提现");map.put("spbill_create_ip", "xxx.xxx.xxx.xxx");String stringSign = WXUtil.createSign(map);String sign = WXPayUtil.MD5(stringSign).toUpperCase();map.put("sign", sign);String data = WXPayUtil.mapToXml(map);File file = new File("apiclient_cert.p12");InputStream in = new FileInputStream(file);char password[] = WXUtil.MCH_ID.toCharArray();java.io.InputStream certStream = in;KeyStore ks = KeyStore.getInstance("PKCS12");ks.load(certStream, password);KeyManagerFactory kmf = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());kmf.init(ks, password);SSLContext sslContext = SSLContext.getInstance("TLS");sslContext.init(kmf.getKeyManagers(), null, new SecureRandom());SSLConnectionSocketFactory sslConnectionSocketFactory = new SSLConnectionSocketFactory(sslContext,new String[] { "TLSv1" }, null, new DefaultHostnameVerifier());BasicHttpClientConnectionManager connManager = new BasicHttpClientConnectionManager();CloseableHttpClient httpClient = HttpClients.custom().setSSLSocketFactory(sslConnectionSocketFactory).build();String url = (new StringBuilder()).append("https://").append("api.mch.weixin.qq.com").append("/mmpaymkttransfers/promotion/transfers").toString();HttpPost httpPost = new HttpPost(url);RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(10000).setConnectTimeout(10000).build();httpPost.setConfig(requestConfig);StringEntity postEntity = new StringEntity(data, "UTF-8");httpPost.addHeader("Content-Type", "text/xml");httpPost.addHeader("User-Agent", (new StringBuilder()).append(WXPayConstants.USER_AGENT).append(" ").append(map.get("mch_id")).toString());httpPost.setEntity(postEntity);CloseableHttpResponse httpResponse = httpClient.execute(httpPost);org.apache.http.HttpEntity httpEntity = httpResponse.getEntity();String reponseString = EntityUtils.toString(httpEntity, "UTF-8");return WXPayUtil.xmlToMap(reponseString);}/*** 微信返回参数解密* @param reqInfo* @return* @throws Exception*/public static Map parseReqInfo(String reqInfo) throws Exception {init();Base64.Decoder decoder = Base64.getDecoder();byte[] base64ByteArr = decoder.decode(reqInfo);String result = new String(cipher.doFinal(base64ByteArr));return WXPayUtil.xmlToMap(result);}public static void init() {String key = getMD5(KEY);SecretKeySpec secretKeySpec = new SecretKeySpec(key.getBytes(), "AES");Security.addProvider(new BouncyCastleProvider());try {cipher = Cipher.getInstance("AES/ECB/PKCS7Padding");cipher.init(Cipher.DECRYPT_MODE, secretKeySpec);} catch (NoSuchAlgorithmException e) {e.printStackTrace();} catch (NoSuchPaddingException e) {e.printStackTrace();} catch (InvalidKeyException e) {e.printStackTrace();}}public static String getMD5(String str) {try {MessageDigest md = MessageDigest.getInstance("MD5");String result = MD5(str, md);return result;} catch (NoSuchAlgorithmException e) {e.printStackTrace();return "";}}public static String MD5(String strSrc, MessageDigest md) {byte[] bt = strSrc.getBytes();md.update(bt);String strDes = bytes2Hex(md.digest());return strDes;}public static String bytes2Hex(byte[] bts) {StringBuffer des = new StringBuffer();String tmp = null;for (int i = 0; i < bts.length; i++) {tmp = (Integer.toHexString(bts[i] & 0xFF));if (tmp.length() == 1) {des.append("0");}des.append(tmp);}return des.toString();}public static String httpClient(String data) throws Exception{BasicHttpClientConnectionManager connManager = new BasicHttpClientConnectionManager();HttpClient httpClient = HttpClientBuilder.create().setConnectionManager(connManager).build();String url = (new StringBuilder()).append("https://").append("api.mch.weixin.qq.com").append("/pay/unifiedorder").toString();HttpPost httpPost = new HttpPost(url);RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(10000).setConnectTimeout(10000).build();httpPost.setConfig(requestConfig);StringEntity postEntity = new StringEntity(data, "UTF-8");httpPost.addHeader("Content-Type", "text/xml");httpPost.addHeader("User-Agent", (new StringBuilder()).append(WXPayConstants.USER_AGENT).append(" ").append(WXUtil.MCH_ID).toString());httpPost.setEntity(postEntity);HttpResponse httpResponse = httpClient.execute(httpPost);org.apache.http.HttpEntity httpEntity = httpResponse.getEntity();String reponseString = EntityUtils.toString(httpEntity, "UTF-8");return reponseString;}}

统一下单 - 微信预支付

@NoArgsConstructor
@Data
@Accessors(chain = true)
public class WeixinPayReqDto {@ApiModelProperty(value="请求参数")private WeixinPayReqData data;@NoArgsConstructor@Data@Accessors(chain=true)public class WeixinPayReqData {@ApiModelProperty(value="总金额")private double totalMoney;@ApiModelProperty(value="订单号")private String out_trade_no;@ApiModelProperty(value="openid")private String openid;}
}

@PostMapping("weixinPay")
public BaseDataResDto<Map<String, Object>> weixinPay(@RequestBody WeixinPayReqDto param) throws Exception {return capitalMainLogService.weixinPay(param, maijiToken);
}

@Override
public BaseDataResDto<Map<String, Object>> weixinPay(WeixinPayReqDto param) throws Exception {// 根据订单号查看订单是否存在ShopingOrder shopingOrder = new ShopingOrder();shopingOrder.setOrderNo(param.getData().getOut_trade_no());ShopingOrder newShopingOrder = shopingOrderMapper.selectOne(shopingOrder);if (newShopingOrder == null) return new BaseDataResDto<>(Status.PARAMETERERROR, "订单编号不存在");if (newShopingOrder.getStatus() != 0) {return new BaseDataResDto<>(Status.PARAMETERERROR, "该订单已支付");}// 校验支付金额和应付金额是否一致if (param.getData().getTotalMoney() != newShopingOrder.getAmount()) {return new BaseDataResDto<>(Status.PARAMETERERROR, "支付金额错误");}String out_trade_no = shopingOrder.getOrderNo() + "_" + (int) (Math.random() * 1000000);Map map = new HashMap();map.put("appid", WXUtil.APP_ID);map.put("mch_id", WXUtil.MCH_ID);map.put("nonce_str", UUID_MD5.getUUID());map.put("sign_type", "MD5");map.put("body", "商品支付");map.put("out_trade_no", out_trade_no);map.put("fee_type", "CNY");map.put("total_fee", (int) (param.getData().getTotalMoney() * 100) + "");map.put("spbill_create_ip", "192.168.100.8");map.put("notify_url", WXUtil.NOTIFY_URL);map.put("trade_type", "APP");map.put("sign", WXPayUtil.MD5(WXUtil.createSign(map)).toUpperCase());// 请求报文 （map转为xml）String data = WXPayUtil.mapToXml(map);Map mapResponse = WXPayUtil.xmlToMap(WXUtil.httpClient(data));BaseDataResDto paramMap = new BaseDataResDto(Status.SUCCESS);Map<String, String> mapWeixinPay = new HashMap<String, String>();if (mapResponse.get("return_code") != null && mapResponse.get("result_code") != null) {mapWeixinPay.put("appid", WXUtil.APP_ID);mapWeixinPay.put("partnerid", WXUtil.MCH_ID);if (mapResponse.get("prepay_id") == null) return new BaseDataResDto<>(Status.PARAMETERERROR);long time = System.currentTimeMillis() / 1000;mapWeixinPay.put("noncestr", Long.toString(time));mapWeixinPay.put("timestamp", Long.toString(time));mapWeixinPay.put("prepayid", (String) mapResponse.get("prepay_id"));mapWeixinPay.put("package", "Sign=WXPay");String signString = WXUtil.createSign(mapWeixinPay);String signs = WXPayUtil.MD5(signString).toUpperCase();mapWeixinPay.put("sign", signs);paramMap.setData(mapWeixinPay);newShopingOrder.setPrepayId((String) mapResponse.get("prepay_id"));newShopingOrder.setNonceStr(map.get("nonce_str") + "");} else {paramMap.setStatus(Status.PARAMETERERROR);}// 保存预支付订单号shopingOrderMapper.updateById(newShopingOrder.setOutTradeNo(out_trade_no));return paramMap;
}

成功返回给安卓/IOS，由他们调起微信收银台发起付款即可。

2. 【微信支付成功回调】（支付结果通知）

支付完成后，微信会把相关支付结果及用户信息通过数据流的形式发送给商户，商户需要接收处理，并按文档规范返回应答。

该链接是通过【统一下单API】中提交的参数notify_url设置，如果链接无法访问，商户将无法接收到微信通知。

通知url必须为直接可访问的url，不能携带参数。

注意：

① 同样的通知可能会多次发送给商户系统。商户系统必须能够正确处理重复的通知。

② 后台通知交互时，如果微信收到商户的应答不符合规范或超时，微信会判定本次通知失败，重新发送通知，直到成功为止（在通知一直不成功的情况下，微信总共会发起多次通知，通知频率为15s/15s/30s/3m/10m/20m/30m/30m/30m/60m/3h/3h/3h/6h/6h - 总计 24h4m），但微信不保证通知最终一定能成功。

③ 在订单状态不明或者没有收到微信支付结果通知的情况下，建议商户主动调用微信支付【查询订单API】确认订单状态。

@XmlRootElement(name = "xml")
@XmlAccessorType(XmlAccessType.FIELD)
@NoArgsConstructor
@Data
@Accessors(chain=true)
public class PayResDto {private String return_msg;private String return_code;private String appid;private String mch_id;private String device_info;private String nonce_str;private String sign;private String result_code;private String err_code;private String err_code_des;private String openid;private String is_subscribe;private String trade_type;private String bank_type;private Integer total_fee;private String fee_type;private Integer cash_fee;private String cash_fee_type;private Integer coupon_fee;private Integer coupon_count;private String coupon_id_$n;private Integer coupon_fee_$n;private String transaction_id;private String out_trade_no;private String attach;private String time_end;
}

import com.github.wxpay.sdk.WXPayUtil;@PostMapping("weixinPayCallBack")
public String weixinPayCallBack(@RequestBody PayResDto param) throws Exception {Map map = capitalMainLogService.weixinPayCallBack(param);return WXPayUtil.mapToXml(map);
}

@Override
public Map weixinPayCallBack(PayResDto param) {Map<String, Object> map = new HashMap<String, Object>();map.put("return_code", "SUCCESS");if (param == null) {map.put("return_msg", "参数为空");return map;}// 根据订单号查看订单信息ShopingOrder shopingOrder = shopingOrderService.selectOne(new EntityWrapper<ShopingOrder>().eq("order_no", param.getOut_trade_no().substring(0, 20)));// 已经付款if (Arrays.asList(1, 2, 3, 5, 6).contains(shopingOrder.getStatus())) {map.put("return_msg", "OK");return map;}shopingOrder.setStatus(1).setPayId(param.getTransaction_id()).setPayDate(newDate()).setOutTradeNo(param.getOut_trade_no()).setPayType(2);// 修改支付状态为成功shopingOrderMapper.updateById(shopingOrder);// 分销distributionService.asyncDistributionFund(shopingOrder);map.put("return_msg", "OK");return map;
}

3. 【查询订单】

接口提供所有微信支付订单的查询，商户可以通过该接口主动查询订单状态，完成下一步的业务逻辑。

需要调用查询接口的情况：

◆ 当商户后台、网络、服务器等出现异常，商户系统最终未接收到支付通知；

◆ 调用支付接口后，返回系统错误或未知交易状态情况；

◆ 调用被扫支付API，返回USERPAYING的状态；

◆ 调用关单或撤销接口API之前，需确认支付状态；

@Bean
public RestTemplate restTemplate() {RestTemplate restTemplate = new RestTemplate();Charset thirdRequest = Charset.forName("UTF-8");// 处理请求中文乱码问题List<HttpMessageConverter<?>> messageConverters = restTemplate.getMessageConverters();for (HttpMessageConverter<?> messageConverter : messageConverters) {if (messageConverter instanceof StringHttpMessageConverter) {((StringHttpMessageConverter) messageConverter).setDefaultCharset(thirdRequest);}if (messageConverter instanceof MappingJackson2HttpMessageConverter) {((MappingJackson2HttpMessageConverter) messageConverter).setDefaultCharset(thirdRequest);}if (messageConverter instanceof AllEncompassingFormHttpMessageConverter) {((AllEncompassingFormHttpMessageConverter) messageConverter).setCharset(thirdRequest);}}return restTemplate;
}

@Autowired
private RestTemplate restTemplate;/** 微信查询订单 */
@PostMapping("weixinOrderQuery")
public Map<String, String> weixinOrderQuery(@RequestParam String out_trade_no)  throws Exception {Map map = new HashMap();map.put("appid", WXUtil.APP_ID);map.put("mch_id", WXUtil.MCH_ID);map.put("nonce_str", UUID_MD5.getUUID());map.put("out_trade_no", out_trade_no);String sign = WXPayUtil.MD5(WXUtil.createSign(map)).toUpperCase();map.put("sign", sign);String data = WXPayUtil.mapToXml(map);String response = restTemplate.postForObject("https://api.mch.weixin.qq.com/pay/orderquery", data, String.class);return WXPayUtil.xmlToMap(response);
}

4. 【退款】

当交易发生之后一段时间内，由于买家或者卖家的原因需要退款时，卖家可以通过退款接口将支付款退还给买家，微信支付将在收到退款请求并且验证成功之后，按照退款规则将支付款按原路退到买家帐号上。

注意：

◆ 交易时间超过一年的订单无法提交退款；

◆ 微信支付退款支持单笔交易分多次退款，多次退款需要提交原支付订单的商户订单号和设置不同的退款单号。申请退款总金额不能超过订单金额。一笔退款失败后重新提交，请不要更换退款单号，请使用原商户退款单号。

◆ 请求频率限制：150qps，即每秒钟正常的申请退款请求次数不超过150次

错误或无效请求频率限制：6qps，即每秒钟异常或错误的退款申请请求不超过6次

◆ 每个支付订单的部分退款次数不能超过50次

◆ 如果同一个用户有多笔退款，建议分不同批次进行退款，避免并发退款导致退款失败

@Override
public BaseResDto executeRefund(String orderRefundId) throws Exception{ShoppingOrderRefundEntity shoppingOrderRefund = shopingOrderRefundService.selectById(orderRefundId).setRefundMiddleTime(new Date()).setStatus(3);//退款中String orderId = shoppingOrderRefund.getOrderId();ShopingOrder shopingOrder = shopingOrderMapper.selectById(orderId)         .setRefundStatus(3);//退款中Double refundMoney = shoppingOrderRefund.getRefundMoney();Double amount = shopingOrder.getAmount();if (refundManey > amount) return BaseResDto.baseResDto(Status.ERROR, "退款金额错误！");Map wxMap = WXUtil.applayRefund(shopingOrder.getUserId(), shopingOrder.getPayId(), shopingOrder.getOutTradeNo(), amount, refundMoney);if (!wxMap.get("result_code").equals("SUCCESS"))return BaseResDto.baseResDto(Status.ERROR, "申请微信退款失败！");// 下面接入自己的业务逻辑...return new BaseResDto(Status.SUCCESS);       
}

5. 【退款回调通知】

当商户申请的退款有结果后（退款状态为：退款成功、退款关闭、退款异常），微信会把相关结果发送给商户，商户需要接收处理，并返回应答。
对后台通知交互时，如果微信收到商户的应答不是成功或超时，微信认为通知失败，微信会通过一定的策略定期重新发起通知，尽可能提高通知的成功率，但微信不保证通知最终能成功（通知频率为15s/15s/30s/3m/10m/20m/30m/30m/30m/60m/3h/3h/3h/6h/6h - 总计 24h4m）。
注意：同样的通知可能会多次发送给商户系统。商户系统必须能够正确处理重复的通知。
推荐的做法是，当收到通知进行处理时，首先检查对应业务数据的状态，判断该通知是否已经处理过，如果没有处理过再进行处理，如果处理过直接返回结果成功。在对业务数据进行状态检查和处理之前，要采用数据锁进行并发控制，以避免函数重入造成的数据混乱。
特别说明：退款结果对重要的数据进行了加密，商户需要用商户秘钥进行解密后才能获得结果通知的内容。

@XmlRootElement(name = "xml")
@XmlAccessorType(XmlAccessType.FIELD)
@NoArgsConstructor
@Data
@Accessors(chain = true)
public class WXRefundReqDto { //严格按照微信官方文档封装的实体类private String return_msg;private String return_code;private String appid;private String mch_id;private String nonce_str;private String req_info;private String transaction_id; //微信订单号private String out_trade_no; //商户订单号private String refund_id; //微信退款单号private String out_refund_no; //商户退款单号private String total_fee; //订单金额private String settlement_total_fee; //应结订单金额private String refund_fee; //申请退款金额private String settlement_refund_fee; //退款金额private String refund_status; //退款状态private String success_time; //退款成功时间private String refund_recv_accout; //退款入账账户private String refund_account; //退款资金来源private String refund_request_source; //退款发起来源}

@PostMapping("refundCallBack")
public String refundCallBack(@RequestBody WXRefundReqDto param) throws Exception {Map map = capitalMainLogService.refundCallBack(param);return WXPayUtil.mapToXml(map);
}

@Override
public Map refundCallBack(WXRefundReqDto param) throws Exception {Map map = new HashMap();if (param == null) {map.put("return_code", "FAIL");map.put("return_msg", "参数为空");return map;}if (!"SUCCESS".equals(param.getReturn_code())) {map.put("return_code", "FAIL");map.put("return_msg", "退款失败");return map;}Map signMap = objectToMap(param);signMap.remove("return_code");signMap.remove("return_msg");signMap.remove("appid");signMap.remove("mch_id");signMap.remove("nonce_str");signMap.remove("req_info");String refundSignString = WXUtil.createSign(signMap);String sign = WXPayUtil.MD5(refundSignString).toUpperCase();// 验证签名if (!sign.equals(param.getReq_info())) {map.put("return_code", "FAIL");map.put("return_msg", "签名错误");}// 根据订单号查看订单信息String order_no = (String) WXUtil.parseReqInfo(param.getReq_info()).get("out_trade_no");ShopingOrder shopingOrder = shopingOrderMapper.selectOne(new ShopingOrder().setOutTradeNo(order_no));// 已经退款if (shopingOrder.getStatus() == 4) {map.put("return_msg", "OK");map.put("return_code", "SUCCESS");return map;}// 修改订单表退款状态     shopingOrder.setRefundStatus(4); //退款成功if (!shopingOrderService.updateById(shopingOrder)) {map.put("return_code", "FAIL");return map;}// 其他业务逻辑自行编写...map.put("return_msg", "OK");map.put("return_code", "SUCCESS");return map;
}

6. 【查询退款】

提交退款申请后，通过调用该接口查询退款状态。退款有一定延时，用零钱支付的退款20分钟内到账，银行卡支付的退款3个工作日后重新查询退款状态。

@Autowired
private RestTemplate restTemplate;/** 查询微信退款 */
@PostMapping("wxRefundQuery")
public Map<String, String> wxRefundQuery(@RequestParam String out_trade_no) throws Exception{Map map = new HashMap();map.put("appid", WXUtil.APP_ID);map.put("mch_id", WXUtil.MCH_ID);map.put("nonce_str", UUID_MD5.getUUID());map.put("out_trade_no", out_trade_no);String sign = WXPayUtil.MD5(WXUtil.createSign(map)).toUpperCase();map.put("sign", sign);String data = WXPayUtil.mapToXml(map);String response = restTemplate.postForObject("https://api.mch.weixin.qq.com/pay/refundquery", data, String.class);return WXPayUtil.xmlToMap(response);
}

7. 【企业付款到零钱】（提现）

使用条件和开通步骤参考官方文档：https://pay.weixin.qq.com/wiki/doc/api/tools/mch_pay.php?chapter=14_1

企业付款为企业提供付款至用户零钱的能力，支持通过API接口付款，或通过微信支付商户平台（pay.weixin.qq.com）网页操作付款。

【使用条件】（切记，博主就被坑过）

◆ 商户号（或同主体其他非服务商商户号）已入驻90日

◆ 截止今日回推30天，商户号（或同主体其他非服务商商户号）连续不间断保持有交易

◆ 登录微信支付商户平台-产品中心，开通企业付款。

◆ spbill_create_ip 必须在商户平台配置好IP白名单

@PostMapping("withdraw")
public BaseResDto withdraw(@RequestParam Bigdecimal money,@RequestHeader("token") String token) {// 验证token，并根据token获取用户实体UserEntity，此处省略...Map map = WXUtil.wxWithdraw(userEntity.getWxOpenId(), userEntity.getRealName(), money); //如果check_name为NO_CHECK，则传昵称也可以if (!("SUCCESS".equals(map.get("return_code")) && "SUCCESS".equals(map.get("result_code"))))return new BaseResDto(Status.PARAMETERERROR, "提现失败");// 此处编写业务逻辑，并记录提现日志return new BaseResDto(Status.SUCCESS);
}

二. 扫码支付

Native支付可分为两种模式，商户根据支付场景选择相应模式。

一般我们电商网站都会选用模式二：https://pay.weixin.qq.com/wiki/doc/api/native.php?chapter=6_5

@RestController
public class WxNativePay {@PostMapping("/wxNativePay")public BaseDataResDto<JSONObject> wxNativePay()  {try{Map map = new HashMap();map.put("appid", WXUtil.APP_ID);map.put("mch_id", WXUtil.MCH_ID);map.put("nonce_str", UUID_MD5.getUUID());map.put("sign_type", "MD5");map.put("body", "商品支付");map.put("out_trade_no", "1234560001");map.put("fee_type", "CNY");map.put("total_fee", 10 + "");map.put("spbill_create_ip", "127.0.0.1");map.put("notify_url", WXUtil.NOTIFY_URL);map.put("trade_type", "NATIVE");map.put("sign", WXPayUtil.MD5(WXUtil.createSign(map)).toUpperCase());// 请求报文 （map转为xml）String data = WXPayUtil.mapToXml(map);Map<String, String> mapResponse = WXPayUtil.xmlToMap(WXUtil.httpClient(data));if (Objects.equals(mapResponse.get("result_code"),"SUCCESS")) {String content = mapResponse.get("code_url");JSONObject json = new JSONObject();json.put("codeUrl", content);return new BaseDataResDto(Status.SUCCESS).setData(json);}} catch (Exception e) {e.printStackTrace();}return new BaseDataResDto(Status.ERROR);}
}