微信小程序支付(java端)

1. 準備

首先導入jar包(maven導入jar包)

<dependency>
    <groupId>com.github.wxpay</groupId>
    <artifactId>wxpay-sdk</artifactId>
    <version>0.0.3</version>
</dependency>

2. 配置類

import java.io.InputStream;

import com.github.wxpay.sdk.WXPayConfig;
import com.qx.rdes.wx.util.PropertiesUtils;

/**
 * 配置類
 *
 * @author 豆漿油條
 * @date 
 **/
public class MyConfig implements WXPayConfig {

    @Override
    public String getAppID() {
    	return "自己的appid";
    }
    
    public String getSecret() {
    	return "自己的祕鑰";
    }
    
    public String getNotifyUrl() {
    	return "回調地址";

    }

    @Override
    public String getMchID() {
    	return "商戶號";
    }

    @Override
    public String getKey() {
    	return "商戶祕鑰";
    }

    @Override
    public InputStream getCertStream() {
        return null;
    }

    @Override
    public int getHttpConnectTimeoutMs() {
        return 8000;
    }

    @Override
    public int getHttpReadTimeoutMs() {
        return 10000;
    }
}

3. 代碼實現

1.微信統一下單接口

/**
     * 微信統一下單接口
     * @return
     */
    @RequestMapping(value = "/doUnifiedOrder", method = RequestMethod.POST)
    public synchronized Map doUnifiedOrder(HttpServletRequest request, HttpServletResponse response) {
//        BaseResponse<Map> response = new BaseResponse<>();
        Map resultMap=new HashMap();
        String openid = "openid";
        MyConfig config = null;
        WXPay wxpay =null;
        try {
            config = new MyConfig();
            wxpay= new WXPay(config);
        } catch (Exception e) {
            e.printStackTrace();
        }
        //生成的隨機字符串
        String nonce_str = WXPayUtil.generateNonceStr();
        //獲取客戶端的ip地址
        //獲取本機的ip地址
        InetAddress addr = null;
        try {
            addr = InetAddress.getLocalHost();
        } catch (UnknownHostException e) {
            e.printStackTrace();
        }
        String spbill_create_ip = addr.getHostAddress();
        //支付金額，需要轉成字符串類型，否則後面的簽名會失敗
        int  total_fee= 100;
        //商品描述
        String body = "描述";
        //商戶訂單號
//      String out_trade_no= WXPayUtil.generateNonceStr();
        String currTime = TenpayUtil.getCurrTime();  
	    // 8位日期  
	    String strTime = currTime.substring(8, currTime.length());  
	    // 四位隨機數  
	    String strRandom = TenpayUtil.buildRandom(4) + "";  
	    // 10位序列號,可以自行調整。  
	    String strReq = currTime + strRandom;  
	    // 訂單號，此處用時間加隨機數生成，商戶根據自己情況調整，只要保持全局唯一就行  
	    String out_trade_no = strReq;  
        //統一下單接口參數
        HashMap<String, String> data = new HashMap<String, String>();
        data.put("appid", config.getAppID());
        data.put("mch_id", config.getMchID());
        data.put("nonce_str", nonce_str);
        data.put("body", body);
        data.put("out_trade_no",out_trade_no);
        data.put("total_fee", String.valueOf(total_fee));
        data.put("spbill_create_ip", spbill_create_ip);
        data.put("notify_url", config.getNotifyUrl());
        data.put("trade_type","JSAPI");
        data.put("openid", openid);
        try {
            Map<String, String> rMap = wxpay.unifiedOrder(data);
            System.out.println("統一下單接口返回: " + rMap);
            String return_code = (String) rMap.get("return_code");
            String result_code = (String) rMap.get("result_code");
            String nonceStr = WXPayUtil.generateNonceStr();
            resultMap.put("nonceStr", nonceStr);
            Long timeStamp = System.currentTimeMillis() / 1000;
            if ("SUCCESS".equals(return_code) && return_code.equals(result_code)) {
                String prepayid = rMap.get("prepay_id");
                resultMap.put("package", "prepay_id="+prepayid);
                resultMap.put("signType", "MD5");
                //這邊要將返回的時間戳轉化成字符串，不然小程序端調用wx.requestPayment方法會報簽名錯誤
                resultMap.put("timeStamp", timeStamp + "");
                //再次簽名，這個簽名用於小程序端調用wx.requesetPayment方法
                resultMap.put("appId",config.getAppID());
                String sign = WXPayUtil.generateSignature(resultMap, config.getKey());
                resultMap.put("paySign", sign);
                System.out.println("生成的簽名paySign : "+ sign);
//              response.setData(resultMap);
                return resultMap;
            }else{
            	resultMap.put("msg", "支付異常,請聯繫管理員");
                return  resultMap;
            }
        } catch (Exception e) {
            e.printStackTrace();
            resultMap.put("msg", "下單失敗!");
            return  resultMap;
        }
    }

2.支付回調

/**
     * 微信小程序支付成功回調函數
     * @param request
     * @param response
     * @throws Exception
     */
    @RequestMapping(value = "/callback")
    public void wxNotify(HttpServletRequest request,HttpServletResponse response) throws Exception{
        BufferedReader br = new BufferedReader(new InputStreamReader((ServletInputStream)request.getInputStream()));
        String line = null;
        StringBuilder sb = new StringBuilder();
        while((line = br.readLine()) != null){
            sb.append(line);
        }
        br.close();
        //sb爲微信返回的xml
        String notityXml = sb.toString();
        String resXml = "";
        System.out.println("接收到的報文：" + notityXml);
        MyConfig config = new MyConfig();
        WXPay wxPay = new WXPay(config);
        Map map = WXPayUtil.xmlToMap(notityXml);
        String returnCode = (String) map.get("return_code");
        //驗證簽名是否正確
        if("SUCCESS".equals(returnCode)){
            //回調驗籤時需要去除sign和空值參數
            Map<String, String> validParams = WXPayUtil.paraFilter(map); 
            //把數組所有元素，按照“參數=參數值”的模式用“&”字符拼接成字符串 
            String validStr = PayUtil.createLinkString(validParams);
            //拼裝生成服務器端驗證的簽名
           String sign = PayUtil.sign(validStr, Configure.getKey(), "utf-8").toUpperCase();
            // 因爲微信回調會有八次之多,所以當第一次回調成功了,那麼我們就不再執行邏輯了
            //根據微信官網的介紹，此處不僅對回調的參數進行驗籤，還需要對返回的金額與系統訂單的金            
            //額進行比對等
            if(sign.equals(map.get("sign"))){
                /**此處添加自己的業務邏輯代碼start**/
                  // bla bla bla....
                /**此處添加自己的業務邏輯代碼end**/
                //通知微信服務器已經支付成功
                resXml = "<xml>" + "<return_code><![CDATA[SUCCESS]]></return_code>"
                        + "<return_msg><![CDATA[OK]]></return_msg>" + "</xml> ";
            } else {
                System.out.println("微信支付回調失敗!簽名不一致");
            }
        }else{
            resXml = "<xml>" + "<return_code><![CDATA[FAIL]]></return_code>"
                    + "<return_msg><![CDATA[報文爲空]]></return_msg>" + "</xml> ";
        }
        System.out.println(resXml);
        System.out.println("微信支付回調數據結束");
        BufferedOutputStream out = new BufferedOutputStream(
                response.getOutputStream());
        out.write(resXml.getBytes());
        out.flush();
        out.close();
    }