记录自己爬过的坑。
大家先感受一下来自微信官方的申请退款API文档带来的魅力。。。
https://pay.weixin.qq.com/wiki/doc/api/jsapi.php?chapter=9_4
下面是实现方法：
先贴出主方法，其中用到的工具类和方法会在下面贴出来
/**
* 微信退款
* @throws Exception
*/
public static String refundFunction(Map<String, Object> map) throws Exception {
//这里的map主要有两个参数（商户号mchId和订单金额totalFee）
String result = "";//这里用于返回处理返回结果
//xml转换为map，这里用于方便自己后面取出打印结果
XmlToMap xmlToMap = new XmlToMap();
//这里是自己封装的一些配置文件，大家可以跳过这一步，下面用到这里会和大家说明
MyConfig config = null;
try {
//加载配置
config = new MyConfig();
} catch (Exception e) {
e.printStackTrace();
}
//获取商户订单号和订单金额
String mchId = map.get("mchId").toString();
//获取订单金额（退款金额默认全部）
//这里是自己做的一些格式的转换，有点笨拙，希望不影响大家的思路
String a = map.get("totalFee")+"";
String b = Double.valueOf(a) + "";
int lastindex = b.indexOf(".");
b = b.substring(0 , lastindex);
int c = Integer.parseInt(b);
// String d = c + "";
// System.out.println("refundMoney--------->"+refundMoney);
String totalFee = c + "";
//获取微信订单号
// String transactionId = map.get("transactionId").toString();
SortedMap<Object,Object> parameters = new TreeMap<Object,Object>();
parameters.put("appid", config.getAppID());//appid
parameters.put("mch_id", config.getMchID());//商户号
parameters.put("nonce_str", CreateNoncestr());//随机数
// parameters.put("transaction_id", transactionId);//微信支付单号
parameters.put("out_trade_no", mchId);//商户订单号
parameters.put("out_refund_no", CreateNoncestr());//我们自己设定的退款申请号，约束为UK
parameters.put("total_fee", totalFee) ;//订单金额 单位为分！！！这里稍微注意一下
parameters.put("refund_fee", totalFee);//退款金额 单位为分！！！
parameters.put("op_user_id", config.getMchID());//操作人员,默认为商户账号
String sign = createSign("utf-8", parameters);
System.out.println("sign---->"+sign);//签名
parameters.put("sign", sign);
//xml和map之间的转换
String reuqestXml = getRequestXml(parameters);
Map<String, Object> xmlMap = XmlToMap.xmlStr2Map(reuqestXml);
KeyStore keyStore = KeyStore.getInstance("PKCS12");
FileInputStream instream = new FileInputStream(new File(config.certPath));//放退款证书的路径
try {
keyStore.load(instream, config.getMchID().toCharArray());//商户号
} finally {
instream.close();
}
//这里导包注意一下，可能会冲突
SSLContext sslcontext = SSLContexts.custom().loadKeyMaterial(keyStore, config.getMchID().toCharArray()).build();//商户号
SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(
sslcontext,
new String[] { "TLSv1" },
null,
SSLConnectionSocketFactory.BROWSER_COMPATIBLE_HOSTNAME_VERIFIER);
CloseableHttpClient httpclient = HttpClients.custom().setSSLSocketFactory(sslsf).build();
try {
HttpPost httpPost = new HttpPost(config.refund_url);//退款接口
System.out.println("executing request" + httpPost.getRequestLine());
StringEntity reqEntity = new StringEntity(reuqestXml);
// 设置类型
reqEntity.setContentType("application/x-www-form-urlencoded");
httpPost.setEntity(reqEntity);
CloseableHttpResponse response = httpclient.execute(httpPost);
try {
HttpEntity entity = response.getEntity();
System.out.println("----------------------------------------");
System.out.println(response.getStatusLine());
if (entity != null) {
System.out.println("Response content length: " + entity.getContentLength());
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(entity.getContent(),"UTF-8"));
System.out.println("bufferedReader.readLine()--->"+bufferedReader.readLine());
String text;
//这里是自己做的输出结果，方便查看错误原因
while ((text = bufferedReader.readLine()) != null) {
System.out.println(text);
if(!text.startsWith("</xml>")) {
text = "<xml>"+text+"</xml>";
Map<String, Object> xmlResultMap = XmlToMap.xmlStr2Map(text);
if(xmlResultMap.get("result_code") != null) {
result = xmlResultMap.get("result_code")+"";
}
}
}
}
EntityUtils.consume(entity);
} finally {
response.close();
}
} finally {
httpclient.close();
}
return result;
}工具类和方法解释：
1、XmlToMap工具类
public class XmlToMap {
//xml形式的字符串转换为map集合
public static Map<String,Object> xmlStr2Map(String xmlStr){
Map<String,Object> map = new HashMap<String,Object>();
Document doc;
try {
doc = DocumentHelper.parseText(xmlStr);
Element root = doc.getRootElement();
List children = root.elements();
if(children != null && children.size() > 0) {
for(int i = 0; i < children.size(); i++) {
Element child = (Element)children.get(i);
map.put(child.getName(), child.getTextTrim());
}
}
} catch (DocumentException e) {
e.printStackTrace();
}
return map;
}
}2、getRequestXml方法
/**
* 转为xml格式
* @param parameters
* @return
*/
public static String getRequestXml(SortedMap<Object,Object> parameters){
StringBuffer sb = new StringBuffer();
sb.append("<xml>");
Set es = parameters.entrySet();
Iterator it = es.iterator();
while(it.hasNext()) {
Map.Entry entry = (Map.Entry)it.next();
String k = (String)entry.getKey();
String v = (String)entry.getValue();
if ("attach".equalsIgnoreCase(k)||"body".equalsIgnoreCase(k)||"sign".equalsIgnoreCase(k)) {
sb.append("<"+k+">"+"<![CDATA["+v+"]]></"+k+">");
}else {
sb.append("<"+k+">"+v+"</"+k+">");
}
}
sb.append("</xml>");
return sb.toString();
}
3、随机字符串生成方法
/**
* 随机字符串
* @return
*/
public static String CreateNoncestr() {
String chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
String res = "";
for (int i = 0; i < 16; i++) {
Random rd = new Random();
res += chars.charAt(rd.nextInt(chars.length() - 1));
}
return res;
} 4、编写签名方法
/**
* 编写签名
* @param charSet
* @param parameters
* @return
* @throws Exception
*/
public static String createSign(String charSet,SortedMap<Object,Object> parameters) throws Exception{
MyConfig myconfig = new MyConfig();
StringBuffer sb = new StringBuffer();
Set es = parameters.entrySet();
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=" + myconfig.getKey());
// String sign = MD5Util.MD5Encode(sb.toString(), charSet).toUpperCase();
String sign = MD5Util.MD5Encode(sb.toString(), charSet).toUpperCase();
// String sign = MD5.MD5Encode(sb.toString(), charSet).toUpperCase();
return sign;
} 5、MD5Util工具类
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" };
}编写时间仓促，代码不足之处希望多多包涵并提出更改意见 [email protected]
大家也可以参考一下这里，这里写的也比较详细