微信APP支付-Java后台实现
1 注册微信开放者平台
开发者平台地址：https://open.weixin.qq.com/
2 成为开发者
3 上传APP
4 开通微信支付功能
5 设置商户号信息
APP 支付能力开通后，微信会给你一个商户号，用户和密码等信息。需要验证商户信息，还需要设置一个加密的密钥字段，这里就不一一细说了。
6 开发接口
微信APP支付接口，是很好调试的，（不像微信公众平台，需要80端口），可以直接在本地就可以进行调试。 具体业务就不细说，直接看代码就懂了。
1 基础信息配置
package com.cat.common.pay.weiChat.config;import java.util.Properties;import com.cat.common.properties.PropertiesUtil;public class WeiChartConfig {
/**
* 预支付请求地址
*/
public static final String PrepayUrl = "https://api.mch.weixin.qq.com/pay/unifiedorder"; /**
* 查询订单地址
*/
public static final String OrderUrl = "https://api.mch.weixin.qq.com/pay/orderquery"; /**
* 关闭订单地址
*/
public static final String CloseOrderUrl = "https://api.mch.weixin.qq.com/pay/closeorder"; /**
* 申请退款地址
*/
public static final String RefundUrl = "https://api.mch.weixin.qq.com/secapi/pay/refund"; /**
* 查询退款地址
*/
public static final String RefundQueryUrl = "https://api.mch.weixin.qq.com/pay/refundquery"; /**
* 下载账单地址
*/
public static final String DownloadBillUrl = "https://api.mch.weixin.qq.com/pay/downloadbill"; /**
* 商户APPID
*/
public static final String AppId = "wxa6d495be83da0beb"; /**
* 商户账户
*/
public static final String MchId = "1321004501"; /**
* 商户秘钥
*/
public static final String AppSercret = "qx2016well03com14wuyou2016xueche"; /**
* 服务器异步通知页面路径
*/
public static String notify_url = getProperties().getProperty("notify_url"); /**
* 页面跳转同步通知页面路径
*/
public static String return_url = getProperties().getProperty("return_url"); /**
* 退款通知地址
*/
public static String refund_notify_url = getProperties().getProperty("refund_notify_url"); /**
* 退款需要证书文件，证书文件的地址
*/
public static String refund_file_path = getProperties().getProperty("refund_file_path"); /**
* 商品名称
*/
public static String subject = getProperties().getProperty("subject"); /**
* 商品描述
*/
public static String body = getProperties().getProperty("body"); private static Properties properties; public static synchronized Properties getProperties(){ if(properties == null){// String path = System.getenv(RSystemConfig.KEY_WEB_HOME_CONF) + "/weichart.properties";//自定义配置文件路径
String path = "d://weichart.properties";//测试路径
properties = PropertiesUtil.getInstance().getProperties(path);
} return properties;
}
}这里是 PropertiesUtil 类
package com.cat.common.properties;import java.io.BufferedInputStream;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import java.util.Properties;public class PropertiesUtil{
private static PropertiesUtil instance; private Properties properties = new Properties(); public synchronized static PropertiesUtil getInstance() { if(null == instance) {
instance = new PropertiesUtil();
} return instance;
} /**
* 获取配置
* @param fileUrl
* @return
*/
public Properties getProperties(String fileUrl){
readProperties(fileUrl); return properties;
} /**
* 读取properties的全部信息
* @param filePath
*/
public void readProperties(String filePath){
InputStream in = null; try{
in = new BufferedInputStream(new FileInputStream(filePath));
properties.load(in);
}catch(Exception e){
e.printStackTrace();
}finally{ try{ if(in != null)
in.close();
}catch(IOException e){
e.printStackTrace();
}
}
}
}2 http /https请求的工具类
其中有需要证书的，也有不需要证书的。
证书是在需要退款接口的时候需要使用，直接把证书放在服务器上，然后传路径
package com.qx.client.common.pay.weichart.util.httpClient;import java.io.BufferedReader;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStreamReader;import java.io.OutputStreamWriter;import java.net.MalformedURLException;import java.net.URL;import java.net.URLConnection;import java.security.KeyStore;import java.util.Map;import javax.net.ssl.SSLContext;import org.apache.commons.httpclient.HttpClient;import org.apache.commons.httpclient.methods.PostMethod;import org.apache.commons.httpclient.methods.StringRequestEntity;import org.apache.commons.httpclient.params.HttpMethodParams;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;public class HttpClientUtil{
public static String post(String url,
Map<String, String> headMap,
Map<String, String> params){
try{
HttpClient httpclient = new HttpClient();
httpclient.getParams().setParameter(HttpMethodParams.HTTP_CONTENT_CHARSET, "UTF-8");
PostMethod httpPost = new PostMethod(url);
if(null != headMap){
for(String key : headMap.keySet()){
httpPost.setRequestHeader(key, headMap.get(key));
}
}
if(null != params){
for(String pkey : params.keySet()){
httpPost.addParameter(pkey, params.get(pkey));
}
}
httpclient.executeMethod(httpPost);
BufferedReader reader = new BufferedReader(new InputStreamReader(httpPost.getResponseBodyAsStream()));
StringBuffer stringBuffer = new StringBuffer();
String str = "";
while((str = reader.readLine()) != null){
stringBuffer.append(str);
}
reader.close();
return stringBuffer.toString();
}catch(Exception e){
e.printStackTrace();
}
return null;
}
public static String postHttplient(String url,
String xmlInfo){
try{
HttpClient httpclient = new HttpClient();
httpclient.getParams().setParameter(HttpMethodParams.HTTP_CONTENT_CHARSET, "UTF-8");
PostMethod httpPost = new PostMethod(url);
httpPost.setRequestEntity(new StringRequestEntity(xmlInfo));
httpclient.executeMethod(httpPost);
BufferedReader reader = new BufferedReader(new InputStreamReader(httpPost.getResponseBodyAsStream()));
StringBuffer stringBuffer = new StringBuffer();
String str = "";
while((str = reader.readLine()) != null){
stringBuffer.append(str);
}
reader.close();
return stringBuffer.toString();
}catch(Exception e){
e.printStackTrace();
}
return null;
} /**
* 需要加密执行的
* @param url
* @param xmlInfo
* @return
* @throws Exception
*/
public static String postHttplientNeedSSL(String url,
String xmlInfo,
String cretPath,
String mrchId)
throws Exception{
//选择初始化密钥文件格式
KeyStore keyStore = KeyStore.getInstance("PKCS12");
//得到密钥文件流
FileInputStream instream = new FileInputStream(new File(cretPath));
try{
//用商户的ID 来解读文件
keyStore.load(instream, mrchId.toCharArray());
}finally{
instream.close();
}
//用商户的ID 来加载
SSLContext sslcontext = SSLContexts.custom().loadKeyMaterial(keyStore, mrchId.toCharArray()).build();
// Allow TLSv1 protocol only
SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslcontext, new String[] { "TLSv1" }, null, SSLConnectionSocketFactory.BROWSER_COMPATIBLE_HOSTNAME_VERIFIER);
//用最新的httpclient 加载密钥
CloseableHttpClient httpclient = HttpClients.custom().setSSLSocketFactory(sslsf).build();
StringBuffer ret = new StringBuffer();
try{
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new StringEntity(xmlInfo));
CloseableHttpResponse response = httpclient.execute(httpPost);
try{
HttpEntity entity = response.getEntity();
if(entity != null){
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(entity.getContent()));
String text;
while((text = bufferedReader.readLine()) != null){ ret.append(text);
}
}
EntityUtils.consume(entity);
}finally{
response.close();
}
}finally{
httpclient.close();
}
return ret.toString();
}
public static String postHtpps(String urlStr,
String xmlInfo){
try{
URL url = new URL(urlStr);
URLConnection con = url.openConnection();
con.setDoOutput(true);
con.setRequestProperty("Pragma:", "no-cache");
con.setRequestProperty("Cache-Control", "no-cache");
con.setRequestProperty("Content-Type", "text/xml;charset=utf-8");
OutputStreamWriter out = new OutputStreamWriter(con.getOutputStream(), "utf-8");
out.write(xmlInfo);
out.flush();
out.close();
BufferedReader br = new BufferedReader(new InputStreamReader(con.getInputStream()));
StringBuffer lines = new StringBuffer();
String line = "";
for(line = br.readLine(); line != null; line = br.readLine()){
lines.append(line);
}
return lines.toString();
}catch(MalformedURLException e){
e.printStackTrace();
}catch(IOException e){
e.printStackTrace();
}
return null;
}
}4 调用API接口
其中包含 XML生成，和解析XML，请求参数字典排序，拼接密钥，MD5加密
这里是核心和微信交互的类。
package com.cat.common.pay.weiChat;import java.net.InetAddress;import java.net.UnknownHostException;import java.util.Arrays;import java.util.Date;import java.util.HashMap;import java.util.Iterator;import java.util.Map;import java.util.Random;import java.util.Set;import org.dom4j.Document;import org.dom4j.DocumentException;import org.dom4j.DocumentHelper;import org.dom4j.Element;import com.cat.common.pay.weiChat.config.WeiChartConfig;import com.cat.common.pay.weiChat.util.HttpClientUtil;public class WeiChartUtil{
/**
* 返回状态码
*/
public static final String ReturnCode = "return_code"; /**
* 返回信息
*/
public static final String ReturnMsg = "return_msg"; /**
* 业务结果
*/
public static final String ResultCode = "result_code"; /**
* 预支付交易会话标识
*/
public static final String PrepayId = "prepay_id"; /**
* 得到微信预付单的返回ID
* @param orderId 商户自己的订单号
* @param totalFee 总金额 （分）
* @return
*/
public static Map<String, String> getPreyId(String orderId,
String totalFee,String schoolLabel){
Map<String, String> reqMap = new HashMap<String, String>();
reqMap.put("appid", WeiChartConfig.AppId);
reqMap.put("mch_id", WeiChartConfig.MchId);
reqMap.put("nonce_str", getRandomString());
reqMap.put("body", "【"+schoolLabel+"】"+ WeiChartConfig.body); //reqMap.put("detail", WeiChartConfig.subject); //非必填
//reqMap.put("attach", "附加数据"); //非必填
reqMap.put("out_trade_no", orderId); //商户系统内部的订单号,
reqMap.put("total_fee", totalFee); //订单总金额，单位为分
reqMap.put("spbill_create_ip", getHostIp()); //用户端实际ip
// reqMap.put("time_start", "172.16.40.18"); //交易起始时间 非必填
// reqMap.put("time_expire", "172.16.40.18"); //交易结束时间 非必填
// reqMap.put("goods_tag", "172.16.40.18"); //商品标记 非必填
reqMap.put("notify_url", WeiChartConfig.notify_url); //通知地址
reqMap.put("trade_type", "APP"); //交易类型
//reqMap.put("limit_pay", "no_credit"); //指定支付方式,no_credit 指定不能使用信用卡支 非必填
reqMap.put("sign", getSign(reqMap));
String reqStr = creatXml(reqMap);
String retStr = HttpClientUtil.postHtpps(WeiChartConfig.PrepayUrl, reqStr); return getInfoByXml(retStr);
} /**
* 关闭订单
* @param orderId 商户自己的订单号
* @return
*/
public static Map<String, String> closeOrder(String orderId){
Map<String, String> reqMap = new HashMap<String, String>();
reqMap.put("appid", WeiChartConfig.AppId);
reqMap.put("mch_id", WeiChartConfig.MchId);
reqMap.put("nonce_str", getRandomString());
reqMap.put("out_trade_no", orderId); //商户系统内部的订单号,
reqMap.put("sign", getSign(reqMap));
String reqStr = creatXml(reqMap);
String retStr = HttpClientUtil.postHtpps(WeiChartConfig.CloseOrderUrl, reqStr); return getInfoByXml(retStr);
} /**
* 查询订单
* @param orderId 商户自己的订单号
* @return
*/
public static String getOrder(String orderId){
Map<String, String> reqMap = new HashMap<String, String>();
reqMap.put("appid", WeiChartConfig.AppId);
reqMap.put("mch_id", WeiChartConfig.MchId);
reqMap.put("nonce_str", getRandomString());
reqMap.put("out_trade_no", orderId); //商户系统内部的订单号,
reqMap.put("sign", getSign(reqMap));
String reqStr = creatXml(reqMap);
String retStr = HttpClientUtil.postHtpps(WeiChartConfig.OrderUrl, reqStr); return retStr;
} /**
* 退款
* @param orderId 商户订单号
* @param refundId 退款单号
* @param totralFee 总金额（分）
* @param refundFee 退款金额（分）
* @param opUserId 操作员ID
* @return
*/
public static Map<String, String> refundWei(String orderId,String refundId,String totralFee,String refundFee,String opUserId){
Map<String, String> reqMap = new HashMap<String, String>();
reqMap.put("appid", WeiChartConfig.AppId);
reqMap.put("mch_id", WeiChartConfig.MchId);
reqMap.put("nonce_str", getRandomString());
reqMap.put("out_trade_no", orderId); //商户系统内部的订单号,
reqMap.put("out_refund_no", refundId); //商户退款单号
reqMap.put("total_fee", totralFee); //总金额
reqMap.put("refund_fee", refundFee); //退款金额
reqMap.put("op_user_id", opUserId); //操作员
reqMap.put("sign", getSign(reqMap));
String reqStr = creatXml(reqMap);
String retStr = ""; try{
retStr = HttpClientUtil.postHttplientNeedSSL(WeiChartConfig.RefundUrl, reqStr, WeiChartConfig.refund_file_path, WeiChartConfig.MchId);
}catch(Exception e){
e.printStackTrace(); return null;
} return getInfoByXml(retStr);
} /**
* 退款查询
* @param refundId 退款单号
* @return
*/
public static Map<String, String> getRefundWeiInfo(String refundId){
Map<String, String> reqMap = new HashMap<String, String>();
reqMap.put("appid", WeiChartConfig.AppId);
reqMap.put("mch_id", WeiChartConfig.MchId);
reqMap.put("nonce_str", getRandomString());
reqMap.put("out_refund_no", refundId); //商户退款单号
reqMap.put("sign", getSign(reqMap));
String reqStr = creatXml(reqMap);
String retStr = HttpClientUtil.postHtpps(WeiChartConfig.RefundQueryUrl, reqStr); return getInfoByXml(retStr);
} /**这个方法 可以自己写，以前我使用的是我公司封装的类，后来很多人找我要JAR包，所以我改成了这样，方便部分人直接使用代码，我自己未测试，不过应该问题不大，欢迎使用有问题的找我。
* 传入map 生成头为XML的xml字符串，例：<xml><key>123</key></xml>
* @param reqMap
* @return
*/
public static String creatXml(Map<String, String> reqMap){
Set<String> set = reqMap.keySet();
StringBuffer b = new StringBuffer();
b.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
b.append("<xml>"); for(String key : set){
b.append("<"+key+">").append(reqMap.get(key)).append("</"+key+">");
}
b.append("</xml>"); return b.toString();
} /**
* 得到加密值
* @param map
* @return
*/
public static String getSign(Map<String, String> map){
String[] keys = map.keySet().toArray(new String[0]);
Arrays.sort(keys);
StringBuffer reqStr = new StringBuffer(); for(String key : keys){
String v = map.get(key); if(v != null && !v.equals("")){
reqStr.append(key).append("=").append(v).append("&");
}
}
reqStr.append("key").append("=").append(WeiChartConfig.AppSercret); return WeiMd5.encode(reqStr.toString()).toUpperCase();
} /**
* 得到10 位的时间戳
* 如果在JAVA上转换为时间要在后面补上三个0
* @return
*/
public static String getTenTimes(){
String t = new Date().getTime()+"";
t = t.substring(0, t.length()-3); return t;
} /**
* 得到随机字符串
* @param length
* @return
*/
public static String getRandomString(){ int length = 32;
String str = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
Random random = new Random();
StringBuffer sb = new StringBuffer(); for(int i = 0; i < length; ++i){ int number = random.nextInt(62);//[0,62)
sb.append(str.charAt(number));
} return sb.toString();
} /**
* 得到本地机器的IP
* @return
*/
private static String getHostIp(){
String ip = ""; try{
ip = InetAddress.getLocalHost().getHostAddress();
}catch(UnknownHostException e){
e.printStackTrace();
} return ip;
} public static Map<String, String> getInfoByXml(String xmlStr){ try{
Map<String, String> m = new HashMap<String, String>();
Document d = DocumentHelper.parseText(xmlStr);
Element root = d.getRootElement(); for ( Iterator<?> i = root.elementIterator(); i.hasNext(); ) {
Element element = (Element) i.next();
String name = element.getName(); if(!element.isTextOnly()){ //不是字符串 跳过。确定了微信放回的xml只有根目录
continue;
}else{
m.put(name, element.getTextTrim());
}
} //对返回结果做校验.去除sign 字段再去加密
String retSign = m.get("sign");
m.remove("sign");
String rightSing = getSign(m); if(rightSing.equals(retSign)){ return m;
}
}catch(DocumentException e){ // TODO Auto-generated catch block
e.printStackTrace();
} return null;
} /**
* 将金额转换成分
* @param fee 元格式的
* @return 分
*/
public static String changeToFen(Double fee){
String priceStr = ""; if(fee != null){ int p = (int)(fee * 100); //价格变为分
priceStr = Integer.toString(p);
} return priceStr;
}
}这个是这里面使用的MD5加密方法
package com.cat.common.pay.weiChat;import java.io.UnsupportedEncodingException;import java.security.MessageDigest;import java.security.NoSuchAlgorithmException;/*
* MD5 算法
*/public class WeiMd5 {
// 全局数组
private final static String[] strDigits = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" }; // 返回形式为数字跟字符串
private static String byteToArrayString(byte bByte) { int iRet = bByte; // System.out.println("iRet="+iRet);
if (iRet < 0) {
iRet += 256;
} int iD1 = iRet / 16; int iD2 = iRet % 16; return strDigits[iD1] + strDigits[iD2];
} // 转换字节数组为16进制字串
private static String byteToString(byte[] bByte) {
StringBuffer sBuffer = new StringBuffer(); for (int i = 0; i < bByte.length; i++) {
sBuffer.append(byteToArrayString(bByte[i]));
} return sBuffer.toString();
} public static String encode(String strObj) {
String resultString = null; try {
resultString = new String(strObj);
MessageDigest md = MessageDigest.getInstance("MD5"); // md.digest() 该函数返回值为存放哈希值结果的byte数组
try{
resultString = byteToString(md.digest(strObj.getBytes("UTF-8")));
}catch(UnsupportedEncodingException e){ // TODO Auto-generated catch block
e.printStackTrace();
}
} catch (NoSuchAlgorithmException ex) {
ex.printStackTrace();
} return resultString;
}
}在微信支付的调试过程中，发现了一个困扰了很长时间的BUG，或者说是一个问题。
就是微信请求预支付的时候如果传了中文，就是body中给的是中文，就会报body不是UTF-8格式。如果强行对字段进行编码，又会报 加密错误。
但是这不是最主要的让人困扰的地方，最让我烦恼的是，我用本地的JDK调试的时候，它是OK 的。 但是用TOMCAT 部署的时候 却一直都不行
在网上有很多的说法，有的说，对body 进行编码转换UTF-8，有的说对整个请求的XML，进行编码。
还有的说编码格式用统一的。iso900…等等，巴拉巴拉的。。
反正我都不行。
最后在大神的帮助下，慢慢梳理，对发送请求的post方法上面想办法。
然后就是下面的 这句关键
public static String postHtpps(String urlStr,
String xmlInfo){ try{
URL url = new URL(urlStr);
URLConnection con = url.openConnection();
con.setDoOutput(true);
con.setRequestProperty("Pragma:", "no-cache");
con.setRequestProperty("Cache-Control", "no-cache");
con.setRequestProperty("Content-Type", "text/xml;charset=utf-8"); //在输入流里面进行转码，是最重要的
OutputStreamWriter out = new OutputStreamWriter(con.getOutputStream(), "utf-8"); out.write(xmlInfo); out.flush(); out.close();
BufferedReader br = new BufferedReader(new InputStreamReader(con.getInputStream()));
StringBuffer lines = new StringBuffer();
String line = ""; for(line = br.readLine(); line != null; line = br.readLine()){
lines.append(line);
} return lines.toString();
}catch(MalformedURLException e){
e.printStackTrace();
}catch(IOException e){
e.printStackTrace();
} return null;
}
}小结：很多人看了我的这篇文章后，就直接COPY了我的代码去使用，然后在我之前发的版本中，有几个生成XML 和 解析XML的 类是我自己封装的JAR包，没有放上来，就很多人找我，加我的QQ留言说 要我给源码。其实那是很简单的一些东西。没必要那么复杂。
我的建议是 我的是一个启发的DEMO。让你能够尽快的上手使用，但是你自己一定需要好好的去看官方的文档，弄懂所有的流程，才能真正的掌握这个技巧。