WeChat payment has become more and more popular now, and there are many products that can quickly access WeChat payment. However, in addition to being convenient, it also makes us gradually rely on third parties to do things and lose the ability to think independently. This time, we plan to share the WeChat payment I have developed before.
1. H5 official account payment
Key points: correctly obtain openId and unify the single interface, correctly process payment result notifications, and correctly configure the payment authorization directory
The payment method of H5 is a widely used method. This payment method is mainly used for web pages with custom menus in WeChat. It relies on the WeChat client installed on the mobile phone. Only higher versions of WeChat support WeChat payment. Please note the following instructions for following my process.
1. Write a page for payment, because it is a test, it is a bit simpler.
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>WeChat payment example</title> <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <form action="oauthServlet" method="POST"> Order number: <input type="text" name="orderNo" /> <input type="submit" value="H5 payment"/> </form> </br></br> <form action="scanCodePayServlet?flag=createCode" method="POST"> Order number: <input type="text" name="orderNo" /> <input type="submit" value="Scan the code to pay"/> </form> </body> </html>
2 Write a servlet for obtaining code through Oauth
package com.debug.weixin.servlet; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.debug.weixin.util.CommonUtil; import com.debug.weixin.util.ServerConfig; public class OauthServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String orderNo=request.getParameter("orderNo"); //Call WeChat Oauth2.0 to get openid String redirectURL=ServerConfig.SERVERDOMAIN+"/BasicWeixin/payServletForH5?orderNo="+orderNo; String redirectURI=""; try { redirectURI=CommonUtil.initOpenId(redirectURL); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } //System.out.println(redirectURI); //RequestDispatcher dis= request.getRequestDispatcher(redirectURI); //dis.forward(request, response); response.sendRedirect(redirectURI); } } 3 After obtaining the code, obtain openId through REDIRECTURI and call the unified single interface
package com.debug.weixin.servlet; import java.io.IOException; import java.io.PrintWriter; import java.util.SortedMap; import java.util.TreeMap; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.debug.weixin.pojo.WeixinOauth2Token; import com.debug.weixin.pojo.WeixinQRCode; import com.debug.weixin.util.AdvancedUtil; import com.debug.weixin.util.CommonUtil; import com.debug.weixin.util.ConfigUtil; import com.debug.weixin.util.PayCommonUtil; public class PayServletForH5 extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String orderNo=request.getParameter("orderNo"); String code=request.getParameter("code"); //Get AccessToken WeixinOauth2Token token=AdvancedUtil.getOauth2AccessToken(ConfigUtil.APPID, ConfigUtil.APP_SECRECT, code); String openId=token.getOpenId(); //Calling WeChat unified payment interface SortedMap<Object, Object> parameters = new TreeMap<Object, Object>(); parameters.put("appid", ConfigUtil.APPID); parameters.put("mch_id", ConfigUtil.MCH_ID); parameters.put("device_info", "1000"); parameters.put("body", "My test order"); parameters.put("nonce_str", PayCommonUtil.CreateNoncestr()); parameters.put("out_trade_no", orderNo); //parameters.put("total_fee", String.valueOf(total)); parameters.put("total_fee", "1"); parameters.put("spbill_create_ip", request.getRemoteAddr()); parameters.put("notify_url", ConfigUtil.NOTIFY_URL); parameters.put("trade_type", "JSAPI"); parameters.put("openid", openId); String sign = PayCommonUtil.createSign("UTF-8", parameters); parameters.put("sign", sign); String requestXML = PayCommonUtil.getRequestXml(parameters); String result = CommonUtil.httpsRequestForStr(ConfigUtil.UNIFIED_ORDER_URL,"POST", requestXML); System.out.println("----------------------------------"); System.out.println(result); System.out.println("----------------------------------"); request.setAttribute("orderNo", orderNo); request.setAttribute("totalPrice", "0.01"); String payJSON=""; try { payJSON=CommonUtil.getH5PayStr(result,request); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } //System.out.println(payJSON); request.setAttribute("unifiedOrder",payJSON); RequestDispatcher dis= request.getRequestDispatcher("h5Pay.jsp"); dis.forward(request, response); } } Calling WeChat to unify a single interface requires attention to the signature algorithm. Only when the signature calculation is correct can the payment be smoothly
public static String getH5PayStr(String result,HttpServletRequest request) throws Exception{ Map<String, String> map = XMLUtil.doXMLParse(result); SortedMap<Object,Object> params = new TreeMap<Object,Object>(); params.put("appId", ConfigUtil.APPID); params.put("timeStamp", Long.toString(new Date().getTime())); params.put("nonceStr", PayCommonUtil.CreateNoncestr()); params.put("package", "prepay_id="+map.get("prepay_id")); params.put("signType", ConfigUtil.SIGN_TYPE); String paySign = PayCommonUtil.createSign("UTF-8", params); params.put("paySign", paySign); //The generation rules of paySign are consistent with the generation rules of Sign String json = JSONObject.fromObject(params).toString(); return json; } 4 Write the final payment interface to adjust WeChat H5 payment
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>WeChat H5 Payment</title> <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0"> <script type="text/javascript"> function jsApiCall(){ WeixinJSBridge.invoke( 'getBrandWCPayRequest',<%=(String)request.getAttribute("unifiedOrder")%>, function(res){ WeixinJSBridge.log(res.err_msg); //alert(res.err_code+res.err_desc+res.err_msg); if(res.err_msg == "get_brand_wcpay_request:ok" ) { alert("Congratulations, payment is successful!"); }else{ alert(res.err_code+res.err_desc+res.err_msg); } } ); } function callpay(){ if (typeof WeixinJSBridge == "undefined"){ if( document.addEventListener ){ document.addEventListener('WeixinJSBridgeReady', jsApiCall, false); }else if (document.attachEvent){ document.attachEvent('WeixinJSBridgeReady', jsApiCall); document.attachEvent('onWeixinJSBridgeReady', jsApiCall); } }else{ jsApiCall(); } } </script> </head> <body> <input type="button" value="pay" onclick="callpay()"/> </body> </html> 5. Processing WeChat payment results notification
package com.debug.weixin.servlet; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.util.Map; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.jdom.JDOMException; import com.debug.weixin.util.PayCommonUtil; import com.debug.weixin.util.XMLUtil; public class PayHandlerServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { InputStream inStream = request.getInputStream(); ByteArrayOutputStream outSteam = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len = 0; while ((len = inStream.read(buffer)) != -1) { outSteam.write(buffer, 0, len); } outSteam.close(); inStream.close(); String result = new String(outSteam.toByteArray(),"utf-8");//Get the return information of WeChat calling our notify_url Map<Object, Object> map=null; try { map = XMLUtil.doXMLParse(result); } catch (JDOMException e) { // TODO Auto-generated catch block e.printStackTrace(); } for(Object keyValue: map.keySet()){ System.out.println(keyValue+"="+map.get(keyValue)); } if (map.get("result_code").toString().equalsIgnoreCase("SUCCESS")) { //Business operations on orders System.out.println("---------------------------OK"); response.getWriter().write(PayCommonUtil.setXML("SUCCESS", "")); //Tell the WeChat server that I received the message, don't call the callback action} } } For the above code, many of them refer to http://blog.csdn.net/u011160656/article/details/41759195, so this part of the code will not be posted. If you need it, you will know it by reading this blog.
2. WeChat scan code to pay (Mode 1)
Key points: You must call the long link to short link interface and correctly configure the scan code to pay callback URL
1 Generate WeChat payment QR code based on the order number
Here are a few ways to generate QR codes:
package com.debug.weixin.util; import com.google.zxing.common.BitMatrix; import javax.imageio.ImageIO; import java.io.File; import java.io.OutputStream; import java.io.IOException; import java.awt.image.BufferedImage; public final class MatrixToImageWriter { private static final int BLACK = 0xFF000000; private static final int WHITE = 0xFFFFFFF; private MatrixToImageWriter() {} public static BufferedImage toBufferedImage(BitMatrix matrix) { int width = matrix.getWidth(); int height = matrix.getHeight(); BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); for (int x = 0; x < width; x++) { for (int y = 0; y < height; y++) { image.setRGB(x, y, matrix.get(x, y) ? BLACK : WHITE); } } return image; } public static void writeToFile(BitMatrix matrix, String format, File file) throws IOException { BufferedImage image = toBufferedImage(matrix); if (!ImageIO.write(image, format, file)) { throw new IOException("Could not write an image of format " + format + " to " + file); } } public static void writeToStream(BitMatrix matrix, String format, OutputStream stream) throws IOException { BufferedImage image = toBufferedImage(matrix); if (!ImageIO.write(image, format, stream)) { throw new IOException("Could not write an image of format " + format); } } } This is a tool class, and there is another method to display the QR code on the interface. CreateQRCode mainly uses code blocks:
public static void createCodeStream(String text,HttpServletResponse response) throws Exception{ // response.setContentType("image/jpeg"); ServletOutputStream sos = response.getOutputStream(); int width = 500; int height = 500; //QR code image format String format = "jpg"; MultiFormatWriter multiFormatWriter = new MultiFormatWriter(); Map hints = new HashMap(); //The encoded hints.put(EncodeHintType.CHARACTER_SET, "UTF-8"); BitMatrix bitMatrix = multiFormatWriter.encode(text, BarcodeFormat.QR_CODE, width, height, hints); //Generate QR code MatrixToImageWriter.writeToStream(bitMatrix, format,sos); sos.close(); } 2. To convert long links to short links to generate QR codes, write a scan code payment callback method and call the unified single interface
package com.debug.weixin.servlet; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.util.Date; import java.util.Map; import java.util.SortedMap; import java.util.TreeMap; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.jdom.JDOMException; import com.debug.weixin.util.CommonUtil; import com.debug.weixin.util.ConfigUtil; import com.debug.weixin.util.CreateQRCode; import com.debug.weixin.util.PayCommonUtil; import com.debug.weixin.util.XMLUtil; import com.mongodb.DBObject; public class ScanCodePayServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String flag=request.getParameter("flag"); if("createCode".equals(flag)){ createPayCode(request,response); }else{ try { wxScanCodeHandler(request,response); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } } public void createPayCode(HttpServletRequest request,HttpServletResponse response){ String orderNo=request.getParameter("orderNo"); SortedMap<Object,Object> paras = new TreeMap<Object,Object>(); paras.put("appid", ConfigUtil.APPID); paras.put("mch_id", ConfigUtil.MCH_ID); paras.put("time_stamp", Long.toString(new Date().getTime())); paras.put("nonce_str", PayCommonUtil.CreateNoncestr()); paras.put("product_id", orderNo);//The product number must be unique String sign = PayCommonUtil.createSign("UTF-8", paras); paras.put("sign", sign); String url = "weixin://wxpay/bizpayurl?sign=SIGN&appid=APPID&mch_id=MCHID&product_id=PRODUCTID&time_stamp=TIMESTAMP&nonce_str=NOCESTR"; String nativeUrl = url.replace("SIGN", sign).replace("APPID", ConfigUtil.APPID).replace("MCHID", ConfigUtil.MCH_ID).replace("PRODUCTID", (String)paras.get("product_id")).replace("TIMESTAMP", (String)paras.get("time_stamp")).replace("NOCESTR", (String)paras.get("nonce_str")); SortedMap<Object,Object> parameters = new TreeMap<Object,Object>(); parameters.put("appid", ConfigUtil.APPID); parameters.put("mch_id", ConfigUtil.MCH_ID); parameters.put("nonce_str", PayCommonUtil.CreateNoncestr()); parameters.put("long_url", CommonUtil.urlEncodeUTF8(nativeUrl)); String sign2 = PayCommonUtil.createSign("UTF-8", parameters); parameters.put("sign", sign2); String requestXML = PayCommonUtil.getRequestXml(parameters); String result =CommonUtil.httpsRequestForStr(ConfigUtil.SHORT_URL, "POST", requestXML); Map<String, String> map=null; try { map = XMLUtil.doXMLParse(result); } catch (JDOMException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } String returnCode = map.get("return_code"); String resultCode = map.get("result_code"); if(returnCode.equalsIgnoreCase("SUCCESS")&&resultCode.equalsIgnoreCase("SUCCESS")){ String shortUrl = map.get("short_url"); //TODO Get shortUrl, write the code to generate the QR code System.out.println("shortUrl="+shortUrl); try { CreateQRCode.createCodeStream(shortUrl,response); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } } public void wxScanCodeHandler(HttpServletRequest request,HttpServletResponse response) throws Exception { InputStream inStream = request.getInputStream(); ByteArrayOutputStream outSteam = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len = 0; while ((len = inStream.read(buffer)) != -1) { outSteam.write(buffer, 0, len); } outSteam.close(); inStream.close(); String result = new String(outSteam.toByteArray(),"utf-8");//Get the return information of WeChat calling our notify_url Map<Object, Object> map=null; try { map = XMLUtil.doXMLParse(result); } catch (JDOMException e) { // TODO Auto-generated catch block e.printStackTrace(); } for(Object keyValue : map.keySet()){ System.out.println(keyValue+"="+map.get(keyValue)); } String orderNo=map.get("product_id").toString(); //After receiving the request parameter, call the unified single interface SortedMap<Object, Object> parameters = new TreeMap<Object, Object>(); parameters.put("appid", ConfigUtil.APPID); parameters.put("mch_id", ConfigUtil.MCH_ID); parameters.put("device_info", "1000"); parameters.put("body", "test code to pay order"); parameters.put("nonce_str", PayCommonUtil.CreateNoncestr()); parameters.put("out_trade_no", map.get("product_id")); //parameters.put("total_fee", String.valueOf(totalPrice)); parameters.put("total_fee", "1"); parameters.put("spbill_create_ip", request.getRemoteAddr()); parameters.put("notify_url", ConfigUtil.NOTIFY_URL); parameters.put("trade_type", "NATIVE"); parameters.put("openid", map.get("openid")); String sign = PayCommonUtil.createSign("UTF-8", parameters); parameters.put("sign", sign); String requestXML = PayCommonUtil.getRequestXml(parameters); String result2 = CommonUtil.httpsRequestForStr(ConfigUtil.UNIFIED_ORDER_URL,"POST", requestXML); System.out.println("-----------------------------统一下单结果---------------------------"); System.out.println(result2); Map<String, String> mm=null; try { mm=getH5PayMap(result2,request); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } //String prepayId=getPrepayId(result2,request); //String returnNoneStr=getReturnNoneStr(result2,request); String prepayId=mm.get("prepay_id"); String returnNoneStr=mm.get("nonce_str");; SortedMap<Object, Object> lastSign = new TreeMap<Object, Object>(); lastSign.put("return_code", "SUCCESS"); lastSign.put("appid", ConfigUtil.APPID); lastSign.put("mch_id", ConfigUtil.MCH_ID); lastSign.put("nonce_str", returnNoneStr); lastSign.put("prepay_id", prepayId); lastSign.put("result_code", "SUCCESS"); lastSign.put("key", ConfigUtil.API_KEY); String lastSignpara = PayCommonUtil.createSign("UTF-8", lastSign); StringBuffer buf=new StringBuffer(); buf.append("<xml>"); buf.append("<return_code>SUCCESS</return_code>"); buf.append("<appid>"+ConfigUtil.APPID+"</appid>"); buf.append("<mch_id>"+ConfigUtil.MCH_ID+"</mch_id>"); buf.append("<mch_id>"+ConfigUtil.MCH_ID+"</mch_id>"); buf.append("<nonce_str>"+returnNoneStr+"</nonce_str>"); buf.append("<prepay_id>"+prepayId+"</prepay_id>"); buf.append("<result_code>SUCCESS</result_code>"); buf.append("<sign>"+lastSignpara+"</sign>"); buf.append("</xml>"); response.getWriter().print(buf.toString()); } public Map<String, String> getH5PayMap(String result,HttpServletRequest request) throws Exception{ Map<String, String> map = XMLUtil.doXMLParse(result); return map; } }Finally, let’s take a look at the WeChat configuration for official account payment and scan code payment:
I hope that through this article, everyone can understand that even if you use Java to make WeChat public accounts and WeChat payment without using the cheating code provided by github, you can develop WeChat applications that satisfy you and your customers. Although the demos given by WeChat are all PHP, these are all clouds. Development language is second, and understanding the underlying layer that interface calls requires is only a compulsory course for programmers.