微信退款接口

import java.io.BufferedReader;import java.io.File;import java.io.FileInputStream;import java.io.InputStreamReader;import java.security.KeyStore;import java.util.ArrayList;import java.util.Collections;import java.util.HashMap;import java.util.Iterator;import java.util.List;import java.util.Map;import java.util.Random;import java.util.Set;import java.util.SortedMap;import java.util.TreeMap;import javax.net.ssl.SSLContext;import org.apache.commons.codec.digest.DigestUtils;import org.apache.http.HttpEntity;import org.apache.http.client.methods.CloseableHttpResponse;import org.apache.http.client.methods.HttpPost;import org.apache.http.conn.ssl.SSLConnectionSocketFactory;import org.apache.http.conn.ssl.SSLContexts;import org.apache.http.entity.StringEntity;import org.apache.http.impl.client.CloseableHttpClient;import org.apache.http.impl.client.HttpClients;import org.apache.http.util.EntityUtils;import org.dom4j.Document;import org.dom4j.DocumentHelper;import org.dom4j.Element;import com.llread.flow.common.Config;import com.llread.flow.common.Constants;import com.llread.flow.common.Dom4jUtil;import com.llread.flow.common.Util;public class Test {public static void main(String[] args) throws Exception{Map params = new HashMap();params.put("appid", Config.getParam(Constants.WX_APP_ID));params.put("mch_id", Config.getParam(Constants.WX_MCH_ID));params.put("nonce_str", Util.getRandomString(16));//单号params.put("out_trade_no", "danhaoceshi001");//退款单号params.put("out_refund_no", "danhaoceshi001");//订单金额params.put("total_fee", "1");//退款金额params.put("refund_fee", "1");//退款原因params.put("refund_desc", "Recharge failed");Document doc = DocumentHelper.createDocument();Element root = DocumentHelper.createElement("xml");doc.setRootElement(root);List keys = new ArrayList(params.keySet());Collections.sort(keys);StringBuilder str = new StringBuilder();for (String key : keys) {String value = params.get(key);if (key.equals("sign")) {Dom4jUtil.setElementCDATAText(root, "/" + key, value);} else {Dom4jUtil.setElementText(root, "/" + key, value);}str.append(key + "=" + value + "&");}str.append("key=" + Config.getParam(Constants.WX_MCH_SECRET));// 签名Dom4jUtil.setElementText(root, "/sign",DigestUtils.md5Hex(str.toString()).toUpperCase());System.out.println("请求参数:"+doc.asXML());KeyStore keyStore = KeyStore.getInstance("PKCS12");FileInputStream instream = new FileInputStream(new File("D:/apiclient_cert.p12"));// 放退款证书的路径try {keyStore.load(instream, Config.getParam(Constants.WX_MCH_ID).toCharArray());} finally {instream.close();}SSLContext sslcontext = SSLContexts.custom().loadKeyMaterial(keyStore, Config.getParam(Constants.WX_MCH_ID).toCharArray()).build();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("https://api.mch.weixin.qq.com/secapi/pay/refund");// 退款接口System.out.println("executing request" + httpPost.getRequestLine());StringEntity reqEntity = new StringEntity(doc.asXML());// 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"));String text;StringBuffer sb = new StringBuffer();while ((text = bufferedReader.readLine()) != null) {//System.out.println("返回参数:"+text);sb.append(text);}System.out.println("返回参数:"+sb);doc = Dom4jUtil.parseXml(sb.toString());root = doc.getRootElement();String code = Dom4jUtil.getElementText(root, "return_code", "FAIL");//退款返回失败if (!code.equals("SUCCESS")) {System.out.println(Dom4jUtil.getElementText(root, "return_msg", "未知错误"));}code = Dom4jUtil.getElementText(root, "result_code", "FAIL");//退款失败原因if (!code.equals("SUCCESS")) {System.out.println(Dom4jUtil.getElementText(root, "err_code", "未知代码")+ ":"+ Dom4jUtil.getElementText(root, "err_code_des", "未知错误"));}}EntityUtils.consume(entity);} finally {response.close();}} finally {httpclient.close();}}

PS：

1.签名错误问题：如果在微信官网验证过签名且签名正确，但是在代码中依旧返回错误，看下你的参数是否包含中文

2.涉及到撤回和退款需要的证书： 微信商户平台-账户中心--API安全出下载