微信官方提供了微信企业账户付款到微信个人零钱接口，提供企业向用户付款的功能，支持企业通过API接口付款，或通过微信支付商户平台网页功能操作付款。该接口并不是直接所有的商户都拥有，企业要开启必须满足以下两个条件：
1、商户号已入驻90日
2、商户号有30天连续正常交易
满足以上条件就可登录微信支付商户平台-产品中心，开通企业付款。
调用的链接地址：接口链接：https://api.mch.weixin.qq.com/mmpaymkttransfers/promotion/transfers
微信官方接口文档提供的调用微信企业付款的参数：
参数中最重要是获取用户openid和调用接口ip，获取openid可以通过公众号获取，app端可以直接获取。具体的代码实现如下：
封装请求微信企业付款的实体类Transfers:
public class Transfers implements Serializable{
private static final long serialVersionUID = 1L;
/** 商户账号appid*/
public String mch_appid;
/** 微信支付商户号*/
public String mchid;
/** 随机串*/
public String nonce_str;
/** 签名*/
public String sign;
/** 商户订单号*/
public String partner_trade_no;
/** 用户id*/
public String openid;
/** 是否校验用户姓名 NO_CHECK：不校验真实姓名 FORCE_CHECK：强校验真实姓名*/
public String check_name;
/** 金额 单位：分*/
public Integer amount;
/** 企业付款描述信息*/
public String desc;
/** ip地址*/
public String spbill_create_ip;
public String getMch_appid() {
return mch_appid;
}
public void setMch_appid(String mch_appid) {
this.mch_appid = mch_appid;
}
public String getMchid() {
return mchid;
}
public void setMchid(String mchid) {
this.mchid = mchid;
}
public String getNonce_str() {
return nonce_str;
}
public void setNonce_str(String nonce_str) {
this.nonce_str = nonce_str;
}
public String getSign() {
return sign;
}
public void setSign(String sign) {
this.sign = sign;
}
public String getPartner_trade_no() {
return partner_trade_no;
}
public void setPartner_trade_no(String partner_trade_no) {
this.partner_trade_no = partner_trade_no;
}
public String getOpenid() {
return openid;
}
public void setOpenid(String openid) {
this.openid = openid;
}
public String getCheck_name() {
return check_name;
}
public void setCheck_name(String check_name) {
this.check_name = check_name;
}
public Integer getAmount() {
return amount;
}
public void setAmount(Integer amount) {
this.amount = amount;
}
public String getDesc() {
return desc;
}
public void setDesc(String desc) {
this.desc = desc;
}
public String getSpbill_create_ip() {
return spbill_create_ip;
}
public void setSpbill_create_ip(String spbill_create_ip) {
this.spbill_create_ip = spbill_create_ip;
}
}
接口部分代码：
private Transfers transfers = new Transfers();
// 构造签名的map
private SortedMap<Object, Object> parameters = new TreeMap<Object, Object>();
// 微信的参数
private WeixinConfigUtils config = new WeixinConfigUtils();
/**
* 微信提现（企业付款）
*/
@Action("weixinWithdraw")
public String weixinWithdraw(){
String openId = request.getParameter("openid");
String ip = request.getParameter("ip");
String money = request.getParameter("money");
String doctorId = request.getParameter("doctorId");
if (StringUtils.isNotBlank(money) && StringUtils.isNotBlank(ip) && StringUtils.isNotBlank(openId) && StringUtils.isNotBlank(doctorId)) {
// 参数组
String appid = config.appid;
String mch_id = config.mch_id;
String nonce_str = RandCharsUtils.getRandomString(16);
//是否校验用户姓名 NO_CHECK：不校验真实姓名 FORCE_CHECK：强校验真实姓名
String checkName ="NO_CHECK";
//等待确认转账金额,ip,openid的来源
Integer amount = Integer.valueOf(money);
String spbill_create_ip = ip;
String partner_trade_no = UuIdUtils.getUUID();
//描述
String desc = "健康由我医师助手提现"+amount/100+"元";
// 参数：开始生成第一次签名
parameters.put("appid", appid);
parameters.put("mch_id", mch_id);
parameters.put("partner_trade_no", partner_trade_no);
parameters.put("nonce_str", nonce_str);
parameters.put("openId", openId);
parameters.put("checkName", checkName);
parameters.put("amount", amount);
parameters.put("spbill_create_ip", spbill_create_ip);
parameters.put("desc", desc);
String sign = WXSignUtils.createSign("UTF-8", parameters);
transfers.setAmount(amount);
transfers.setCheck_name(checkName);
transfers.setDesc(desc);
transfers.setMch_appid(appid);
transfers.setMchid(mch_id);
transfers.setNonce_str(nonce_str);
transfers.setOpenid(openId);
transfers.setPartner_trade_no(partner_trade_no);
transfers.setSign(sign);
transfers.setSpbill_create_ip(spbill_create_ip);
String xmlInfo = HttpXmlUtils.transferXml(transfers);
try {
CloseableHttpResponse response = HttpUtil.Post(weixinConstant.WITHDRAW_URL, xmlInfo, true);
String transfersXml = EntityUtils.toString(response.getEntity(), "utf-8");
Map<String, String> transferMap = HttpXmlUtils.parseRefundXml(transfersXml);
if (transferMap.size()>0) {
if (transferMap.get("result_code").equals("SUCCESS") && transferMap.get("return_code").equals("SUCCESS")) {
//成功需要进行的逻辑操作，
}
}
System.out.println("成功");
} catch (Exception e) {
log.error(e.getMessage());
throw new BasicRuntimeException(this, "企业付款异常" + e.getMessage());
}
}else {
System.out.println("失败");
}
return NONE;
}
产生随机串部分代码：
public class RandCharsUtils {
private static SimpleDateFormat df = new SimpleDateFormat("yyyyMMddHHmmss");
public static String getRandomString(int length) { //length表示生成字符串的长度
String base = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz";
Random random = new Random();
StringBuffer sb = new StringBuffer();
int number = 0;
for (int i = 0; i < length; i++) {
number = random.nextInt(base.length());
sb.append(base.charAt(number));
}
return sb.toString();
}
}
生成签名：
public class WXSignUtils {
/**
* 微信支付签名算法sign
* @param characterEncoding
* @param parameters
* @return
*/
@SuppressWarnings("rawtypes")
public static String createSign(String characterEncoding,SortedMap<Object,Object> parameters){
StringBuffer sb = new StringBuffer();
Set es = parameters.entrySet();//所有参与传参的参数按照accsii排序（升序）
Iterator it = es.iterator();
while(it.hasNext()) {
Map.Entry entry = (Map.Entry)it.next();
String k = (String)entry.getKey();
Object v = entry.getValue();
if(null != v && !"".equals(v)
&& !"sign".equals(k) && !"key".equals(k)) {
sb.append(k + "=" + v + "&");
}
}
sb.append("key=" + weixinConstant.KEY);
String sign = MD5Util.MD5Encode(sb.toString(), characterEncoding).toUpperCase();
return sign;
}
}
md5部分代码:
import java.security.MessageDigest;
public class MD5Util {
private static String byteArrayToHexString(byte b[]) {
StringBuffer resultSb = new StringBuffer();
for (int i = 0; i < b.length; i++)
resultSb.append(byteToHexString(b[i]));
return resultSb.toString();
}
private static String byteToHexString(byte b) {
int n = b;
if (n < 0)
n += 256;
int d1 = n / 16;
int d2 = n % 16;
return hexDigits[d1] + hexDigits[d2];
}
public static String MD5Encode(String origin, String charsetname) {
String resultString = null;
try {
resultString = new String(origin);
MessageDigest md = MessageDigest.getInstance("MD5");
if (charsetname == null || "".equals(charsetname))
resultString = byteArrayToHexString(md.digest(resultString
.getBytes()));
else
resultString = byteArrayToHexString(md.digest(resultString
.getBytes(charsetname)));
} catch (Exception exception) {
}
return resultString;
}
private static final String hexDigits[] = { "0", "1", "2", "3", "4", "5",
"6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };
}
构造xml：
/**
* 构造企业付款xml参数
* @param xml
* @return
*/
public static String transferXml(Transfers transfers){
xStream.autodetectAnnotations(true);
xStream.alias("xml", Transfers.class);
return xStream.toXML(transfers);
}
向微信发送xml请求（验证证书）部分代码：
public class HttpUtil {
/**
* 发送post请求
*
* @param url
* 请求地址
* @param outputEntity
* 发送内容
* @param isLoadCert
* 是否加载证书
*/
public static CloseableHttpResponse Post(String url, String outputEntity, boolean isLoadCert) throws Exception {
HttpPost httpPost = new HttpPost(url);
// 得指明使用UTF-8编码，否则到API服务器XML的中文不能被成功识别
httpPost.addHeader("Content-Type", "text/xml");
httpPost.setEntity(new StringEntity(outputEntity, "UTF-8"));
if (isLoadCert) {
// 加载含有证书的http请求
return HttpClients.custom().setSSLSocketFactory(CertUtil.initCert()).build().execute(httpPost);
} else {
return HttpClients.custom().build().execute(httpPost);
}
}
}
加载证书部分代码：（加载证书需要注意证书放置位置在项目下的webapp中建文件夹，linux单独防止只要地址配置正确即可。）
import java.io.File;
import java.io.FileInputStream;
import java.security.KeyStore;
import javax.net.ssl.SSLContext;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.ssl.SSLContexts;
/**
* 加载证书的类
* @author
* @since 2017/08/16
*/
@SuppressWarnings("deprecation")
public class CertUtil {
private static WeixinConfigUtils config = new WeixinConfigUtils();
/**
* 加载证书
*/
public static SSLConnectionSocketFactory initCert() throws Exception {
FileInputStream instream = null;
KeyStore keyStore = KeyStore.getInstance("PKCS12");
instream = new FileInputStream(new File(weixinConstant.PATH));
keyStore.load(instream, config.mch_id.toCharArray());
if (null != instream) {
instream.close();
}
SSLContext sslcontext = SSLContexts.custom().loadKeyMaterial(keyStore,config.mch_id.toCharArray()).build();
SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslcontext, new String[]{"TLSv1"}, null, SSLConnectionSocketFactory.BROWSER_COMPATIBLE_HOSTNAME_VERIFIER);
return sslsf;
}
}
加载配置文件部分代码：
@SuppressWarnings("unused")
public class WeixinConfigUtils {
private static final Log log = LogFactory.getLog(WeixinConfigUtils.class);
public static String appid;
public static String mch_id;
public static String notify_url;
public static String order_notify_url;
public static String doctor_notify_url;
static {
try{
InputStream is = WeixinConfigUtils.class.getResourceAsStream("/weixin.properties");
Properties properties = new Properties();
properties.load(is);
appid = properties.getProperty("weixin.appid");
mch_id = properties.getProperty("weixin.mch_id");
notify_url = properties.getProperty("weixin.notify_url");
order_notify_url = properties.getProperty("weixin.order_notify_url");
doctor_notify_url = properties.getProperty("weixin.doctor_notify_url");
}catch(Exception ex){
log.debug("加载配置文件："+ex.getMessage());
}
}
}
获取返回的xml参数并解析为map：
/**
* 解析申请退款之后微信返回的值并进行存库操作
* @throws IOException
* @throws JDOMException
*/
public static Map<String, String> parseRefundXml(String refundXml) throws JDOMException, IOException{
ParseXMLUtils.jdomParseXml(refundXml);
StringReader read = new StringReader(refundXml);
// 创建新的输入源SAX 解析器将使用 InputSource 对象来确定如何读取 XML 输入
InputSource source = new InputSource(read);
// 创建一个新的SAXBuilder
SAXBuilder sb = new SAXBuilder();
// 通过输入源构造一个Document
org.jdom.Document doc;
doc = (org.jdom.Document) sb.build(source);
org.jdom.Element root = doc.getRootElement();// 指向根节点
List<org.jdom.Element> list = root.getChildren();
Map<String, String> refundOrderMap = new HashMap<String, String>();
if(list!=null&&list.size()>0){
for (org.jdom.Element element : list) {
refundOrderMap.put(element.getName(), element.getText());
}
return refundOrderMap;
}
return null;
}
调用时候主要是获取openid和调起接口的ip（ip十分重要，微信在收到xml后会校验传过去的ip和微信获取的调起接口ip是否一致）
在调用时候当返回错误码为“SYSTEMERROR”时，一定要使用原单号重试，否则可能造成重复支付等资金风险。
微信官方文档提供有相关的参数错误码
