java實(shí)現(xiàn)微信小程序支付

準(zhǔn)備工作

請(qǐng)仔細(xì)閱讀微信支付文檔 微信支付文檔地址
到微信公眾平臺(tái)開通微信小程序應(yīng)用得到 appid 和 secret

支付代碼

/**
     * @param orderNo    訂單號(hào)
     * @param amount     訂單總金額
     * @param deviceCode 設(shè)備編號(hào)
      * @DESCRIPTION: 訂單支付
     * @return: ResponseData
     */
    public ResponseData payOrder(String openid, String orderNo, double amount,  HttpServletRequest request) {

        log.info("======================= 發(fā)起微信預(yù)支付請(qǐng)求，調(diào)用統(tǒng)一下單開始 =======================");
        log.info("準(zhǔn)備請(qǐng)求數(shù)據(jù)...");
        try {
            //這里可以校驗(yàn)訂單是否存在、是否支付
          
          //生成需要的參數(shù)集合
            Map<String, String> packageParams = this.createPackageParams(orderItemDto, openid, amount, request);

            //MD5運(yùn)算生成簽名，這里是第一次簽名，用于調(diào)用統(tǒng)一下單接口（簽名中所有字符大寫toUpperCase()）
            //WeChat.KEY：微信支付的商戶密鑰，需要在微信后臺(tái)設(shè)置，包括后面用到的 KEY 都是這個(gè)值
            String mySign = this.sign(this.createLinkString(packageParams), WeChat.KEY, "utf-8").toUpperCase();
            packageParams.put("sign", mySign);
            log.info("==== 第一次簽名：" + mySign + " ====\n\t");

            //拼接統(tǒng)一下單接口使用的xml數(shù)據(jù)，要將上一步生成的簽名一起拼接進(jìn)去
            String xml = this.GetMapToXML(packageParams);

            log.info("統(tǒng)一下單接口請(qǐng)求的拼接XML數(shù)據(jù)【" + xml + "】\n\t");

            //調(diào)用統(tǒng)一下單接口，并接受返回的結(jié)果
            String result = httpUtils .httpRequest(WeChat.PAY_URL, "POST", xml);

            if (ToolUtil.isEmpty(result)) {
                log.info("調(diào)用統(tǒng)一下單接口返回的XML數(shù)據(jù)為空，支付失敗");
                return ResponseData.error("支付失敗");
            }

            log.info("統(tǒng)一下單接口返回的XML數(shù)據(jù)【" + result + "】\n\t");
            // 將解析結(jié)果存儲(chǔ)在HashMap中
            Map map = this.doXMLParse(result);

            //返回給小程序端需要的參數(shù)
            Map<String, Object> wxResponse = new HashMap<>();
            if (WeChat.SUCCESS.equals(map.get("return_code")) && WeChat.SUCCESS.equals(map.get("result_code"))) {

                //這里可以寫你的業(yè)務(wù)邏輯，看具體情況,一般業(yè)務(wù)邏輯會(huì)寫在支付回調(diào)函數(shù)里面
                
                Long timeStamp = System.currentTimeMillis() / 1000;
                wxResponse.put("nonceStr", packageParams.get("nonce_str"));
                wxResponse.put("package", "prepay_id=" + map.get("prepay_id"));
                //這邊要將返回的時(shí)間戳轉(zhuǎn)化成字符串，不然小程序端調(diào)用wx.requestPayment方法會(huì)報(bào)簽名錯(cuò)誤
                wxResponse.put("timeStamp", timeStamp + "");
                //拼接簽名需要的參數(shù)
                String stringSignTemp = "appId=" + appid + "&nonceStr=" + packageParams.get("nonce_str") + "&package=prepay_id=" + map.get("prepay_id") + "&signType=MD5&timeStamp=" + timeStamp;

                //再次簽名，這個(gè)簽名用于小程序端調(diào)用wx.requesetPayment方法
                String paySign = this.sign(stringSignTemp, WeChat.KEY, "utf-8").toUpperCase();
                log.info("==== 第二次簽名：" + paySign + " ====");
                wxResponse.put("paySign", paySign);

            } else {
                log.info("調(diào)用統(tǒng)一下單接口返回異常 return_code【" + map.get("return_code") + "】" + " result_code【" + map.get("result_code") + "】 支付失敗");
                return null;
            }

            wxResponse.put("appid", appid);
            wxResponse.put("orderNo", orderNo);
            log.info("======================= 發(fā)起微信支付請(qǐng)求，調(diào)用統(tǒng)一下單結(jié)束 =======================");
            return ResponseData.success(wxResponse);

        } catch (Exception e) {
            log.info("調(diào)用統(tǒng)一下單接口異常：" + e.getMessage());
            log.info("用戶【" + openid + "】支付失敗");
        }
        return ResponseData.error("支付失敗");
    }

簽名類

簽名請(qǐng)參照微信官方簽名算法 地址：簽名算法

/**
     * 簽名字符串
     *
     * @param text          需要簽名的字符串
     * @param key           商戶平臺(tái)設(shè)置的密鑰
     * @param input_charset 編碼格式
     * @return 簽名結(jié)果
     */
    public static String sign(String text, String key, String input_charset) {
        text = text + "&key=" + key;
        return DigestUtils.md5Hex(getContentBytes(text, input_charset));
    }

轉(zhuǎn)換xml

public static String GetMapToXML(Map<String, String> param) {
        StringBuffer sb = new StringBuffer();
        sb.append("<xml>");
        for (Map.Entry<String, String> entry : param.entrySet()) {
            sb.append("<" + entry.getKey() + ">");
            sb.append(entry.getValue());
            sb.append("</" + entry.getKey() + ">");
        }
        sb.append("</xml>");
        return sb.toString();
    }

解析xml

/**
     * 解析xml,返回第一級(jí)元素鍵值對(duì)。如果第一級(jí)元素有子節(jié)點(diǎn)，則此節(jié)點(diǎn)的值是子節(jié)點(diǎn)的xml數(shù)據(jù)。
     *
     * @param strxml
     * @return
     * @throws org.jdom2.JDOMException
     * @throws IOException
     */
    public static Map doXMLParse(String strxml) throws Exception {
        if (stringUtils.isEmpty(strxml)) {
            return null;
        }
        Map m = new HashMap();
        InputStream in = String2Inputstream(strxml);
        SAXBuilder builder = new SAXBuilder();
        Document doc = builder.build(in);
        Element root = doc.getRootElement();
        List list = root.getChildren();
        Iterator it = list.iterator();
        while (it.hasNext()) {
            Element e = (Element) it.next();
            String k = e.getName();
            String v = "";
            List children = e.getChildren();
            if (children.isEmpty()) {
                v = e.getTextNormalize();
            } else {
                v = getChildrenText(children);
            }
            m.put(k, v);
        }
        //關(guān)閉流
        in.close();
        return m;
    }

排序并按規(guī)則拼接

/**
     * 把數(shù)組所有元素排序，并按照“參數(shù)=參數(shù)值”的模式用“&”字符拼接成字符串
     *
     * @param params 需要排序并參與字符拼接的參數(shù)組
     * @return 拼接后字符串
     */
    public static String createLinkString(Map<String, String> params) {
        List<String> keys = new ArrayList<>(params.keySet());
        Collections.sort(keys);
        String prestr = "";
        for (int i = 0; i < keys.size(); i++) {
            String key = keys.get(i);
            String value = params.get(key);
            if (i == keys.size() - 1) {
                // 拼接時(shí)，不包括最后一個(gè)&字符
                prestr = prestr + key + "=" + value;
            } else {
                prestr = prestr + key + "=" + value + "&";
            }
        }
        return prestr;
    }

參數(shù)集合

根據(jù)微信支付文檔的參數(shù)來配置 微信支付文檔地址

private Map<String, String> createPackageParams(OrderItemDto orderItemDto, String openid, double amount, HttpServletRequest request) {

        //支付金額，字符串類型，單位 分
        String total_fee = String.valueOf((int) (amount * 100));
        //生成的隨機(jī)字符串
        String nonce_str = PayUtil.getRandomStringByLength(32);
        //設(shè)置商戶訂單號(hào)(年月日+六位酒店id，不夠補(bǔ)零+隨機(jī)4位 例：20190525000001a2sa)
        String out_trade_no = "";
        //獲取客戶端的ip地址
        String spbill_create_ip = PayUtil.getIpAddr(request);

        //組裝參數(shù)，用戶生成統(tǒng)一下單接口的簽名
        Map<String, String> packageParams = new HashMap<>();
        packageParams.put("appid", appid);
        packageParams.put("mch_id", WeChat.MCH_ID);
        packageParams.put("nonce_str", nonce_str);
        packageParams.put("body", WeChat.PAY_ORDER_BODY);
        //商戶訂單號(hào),自己的訂單ID
        packageParams.put("out_trade_no", out_trade_no);
        //支付金額，這邊需要轉(zhuǎn)成字符串類型，否則后面的簽名會(huì)失敗
        packageParams.put("total_fee", total_fee);
        //客戶端ip
        packageParams.put("spbill_create_ip", spbill_create_ip);
        //支付成功后的回調(diào)地址
        packageParams.put("notify_url", WeChat.NOTIFY_URL);
        //支付方式
        packageParams.put("trade_type", WeChat.TRADETYPE);
        //用戶的openID，自己獲取
        packageParams.put("openid", openid + "");

        return packageParams;
    }

http工具類

import lombok.extern.slf4j.Slf4j;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.ssl.SSLContexts;
import org.apache.http.util.EntityUtils;

import javax.net.ssl.SSLContext;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.security.KeyStore;

@Slf4j
public class httpUtils {

    // 連接超時(shí)時(shí)間，默認(rèn)10秒
    private static int socketTimeout = 10000;
    // 傳輸超時(shí)時(shí)間，默認(rèn)30秒
    private static int connectTimeout = 30000;
    // HTTP請(qǐng)求器
    private static CloseableHttpClient httpClient;
    // 請(qǐng)求器的配置
    private static RequestConfig requestConfig;

    /**
     * 加載證書
     */
    private static void initCert() throws Exception {
        // 證書密碼，默認(rèn)為商戶ID
        String key = "";
        // 商戶證書的路徑
        //public static final String CERT_PATH = "E:/workspace/apiclient_cert.p12"; //本地路徑
        String CERT_PATH = "/usr/local/dev/guns/cert/"; // 服務(wù)器路徑
        String path = CERT_PATH + "qcdr_cert.p12";

        InputStream instream = null;
        try {
            // 讀取本機(jī)存放的PKCS12證書文件
            instream = new FileInputStream(new File(path));

            /*ClassPathResource classPathResource = new ClassPathResource(path);
            //獲取文件流
            instream = classPathResource.getInputStream();
            instream = Thread.currentThread().getContextClassLoader().getResourceAsStream(path);*/
        } catch (Exception e) {
            log.error("商戶證書不正確-->>" + e);
        }
        try {
            // 指定讀取證書格式為PKCS12
            KeyStore keyStore = KeyStore.getInstance("PKCS12");
            // 指定PKCS12的密碼(商戶ID)
            keyStore.load(instream, key.toCharArray());

            SSLContext sslcontext = SSLContexts.custom().loadKeyMaterial(keyStore, key.toCharArray()).build();
            // 指定TLS版本
            SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslcontext, new String[]{"TLSv1"}, null, SSLConnectionSocketFactory.BROWSER_COMPATIBLE_HOSTNAME_VERIFIER);
            // 設(shè)置httpclient的SSLSocketFactory
            httpClient = HttpClients.custom().setSSLSocketFactory(sslsf).build();
        } catch (Exception e) {
            log.error("商戶秘鑰不正確-->>" + e);
        } finally {
            instream.close();
        }
    }

    /**
     * 通過Https往API post xml數(shù)據(jù)
     *
     * @param url    退款地址
     * @param xmlObj 要提交的XML數(shù)據(jù)對(duì)象
     * @return
     */
    public static String postData(String url, String xmlObj) {
        // 加載證書
        try {
            initCert();
        } catch (Exception e) {
            e.printStackTrace();
        }
        String result = null;
        HttpPost httpPost = new HttpPost(url);
        // 得指明使用UTF-8編碼，否則到API服務(wù)器XML的中文不能被成功識(shí)別
        StringEntity postEntity = new StringEntity(xmlObj, "UTF-8");
        httpPost.addHeader("Content-Type", "text/xml");
        httpPost.setEntity(postEntity);
        // 根據(jù)默認(rèn)超時(shí)限制初始化requestConfig
        requestConfig = RequestConfig.custom()
                .setSocketTimeout(socketTimeout)
                .setConnectTimeout(connectTimeout)
                .build();
        // 設(shè)置請(qǐng)求器的配置
        httpPost.setConfig(requestConfig);
        try {
            HttpResponse response = null;
            try {
                response = httpClient.execute(httpPost);
            } catch (IOException e) {
                e.printStackTrace();
            }
            HttpEntity entity = response.getEntity();
            try {
                result = EntityUtils.toString(entity, "UTF-8");
            } catch (IOException e) {
                e.printStackTrace();
            }
        } finally {
            httpPost.abort();
        }
        return result;
    }

    /**
     * @param requestUrl    請(qǐng)求地址
     * @param requestMethod 請(qǐng)求方法
     * @param outputStr     參數(shù)
     */
    public static String httpRequest(String requestUrl, String requestMethod, String outputStr) {
        // 創(chuàng)建SSLContext
        StringBuffer buffer = null;
        try {
            URL url = new URL(requestUrl);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod(requestMethod);
            conn.setDoOutput(true);
            conn.setDoInput(true);
            conn.connect();
            //往服務(wù)器端寫內(nèi)容
            if (null != outputStr) {
                OutputStream os = conn.getOutputStream();
                os.write(outputStr.getBytes("utf-8"));
                os.close();
            }
            // 讀取服務(wù)器端返回的內(nèi)容
            InputStream is = conn.getInputStream();
            InputStreamReader isr = new InputStreamReader(is, "utf-8");
            BufferedReader br = new BufferedReader(isr);
            buffer = new StringBuffer();
            String line = null;
            while ((line = br.readLine()) != null) {
                buffer.append(line);
            }
            br.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return buffer.toString();
    }
}

下面是小程序支付回調(diào)函數(shù)

回調(diào)函數(shù)的路徑需要放在上面支付的參數(shù)集合里，這樣才能收到微信支付結(jié)果通知，通知url必須為外網(wǎng)可訪問的url，不能攜帶參數(shù)
詳細(xì)情況可以看 微信支付文檔

回調(diào)函數(shù)代碼

/**
     * 支付回調(diào)函數(shù)
     */
    public void payOrderCallback(HttpServletRequest request, HttpServletResponse response) {
        log.info("======================= 微信支付回調(diào)開始 =======================");

        //通知微信服務(wù)器已經(jīng)支付是否成功
        String resXml = "<xml>";
        try {
            BufferedReader br = new BufferedReader(new InputStreamReader(request.getInputStream()));

            String line;
            StringBuilder sb = new StringBuilder();
            while ((line = br.readLine()) != null) {
                sb.append(line);
            }
            br.close();
            String notityXml = sb.toString();
            log.info("微信回調(diào)信息：" + notityXml);

            //解析回調(diào)xml
            Map map = this.doXMLParse(notityXml);

            //獲得回調(diào)狀態(tài)碼
            String returnCode = (String) map.get("return_code");
            String resultCode = (String) map.get("result_code");
            log.info("微信回調(diào)狀態(tài)碼return_code【 " + returnCode + " 】");

            if ("SUCCESS".equals(returnCode) && returnCode.equals(resultCode)) {
                log.info("微信支付狀態(tài)碼result_code【 " + resultCode + " 】");

                //獲取返回的金額與系統(tǒng)訂單的金額進(jìn)行比對(duì)
                String totalFee = map.get("total_fee").toString();
                //查詢出訂單金額
                QcOrder order = orderMapper.selectByOrderNo(map.get("out_trade_no").toString());
                log.info("微信返回訂單金額【" + totalFee + "分】 系統(tǒng)訂單金額【" + (int) (order.getAmount() * 100) + "分】");

				//根據(jù)自己需求校驗(yàn)，此處官方推薦校驗(yàn)金額
                //根據(jù)微信官網(wǎng)的介紹，此處不僅對(duì)回調(diào)的參數(shù)進(jìn)行驗(yàn)簽，還需要對(duì)返回的金額與系統(tǒng)訂單的金額進(jìn)行比對(duì)等
                if (PayUtil.verify(map, WeChat.KEY, "utf-8")) {
                    if (totalFee.equals(String.valueOf((int) (order.getAmount() * 100)))) {
					  //到這里就已經(jīng)支付成功了，可以添加業(yè)務(wù)邏輯了
                       
                       //返回給微信支付成功的信息
                        resXml += "<return_code><![CDATA[SUCCESS]]></return_code><return_msg><![CDATA[OK]]></return_msg>";
                    } else {
                        resXml += WeChat.CALLBACK_RETURN_FAIL + "<return_msg><![CDATA[支付金額錯(cuò)誤]]></return_msg>";
                        log.info("微信回調(diào)失敗，支付金額錯(cuò)誤。" + "微信返回訂單金額【" + totalFee + "分】 系統(tǒng)訂單金額【" + (int) (order.getAmount() * 100) + "分】");
                    }
                } else {
                    resXml += WeChat.CALLBACK_RETURN_FAIL + "<return_msg><![CDATA[簽名校驗(yàn)錯(cuò)誤]]></return_msg>";
                    log.info("微信回調(diào)簽名驗(yàn)證【 失敗 】");
                }
            } else {
                resXml += WeChat.CALLBACK_RETURN_FAIL + "<return_msg><![CDATA[報(bào)文為空]]></return_msg>";
                log.info("微信回調(diào)【 失敗 】");
            }
        } catch (Exception e) {
            resXml += WeChat.CALLBACK_RETURN_FAIL + "<return_msg><![CDATA[回調(diào)異常]]></return_msg>";
            log.info("微信支付回調(diào)異常：" + e.getMessage());
            e.printStackTrace();
        }

        resXml += "</xml> ";
        try {
            BufferedOutputStream out = new BufferedOutputStream(response.getOutputStream());
            out.write(resXml.getBytes());
            out.flush();
        } catch (Exception e) {
            log.info("給微信返回狀態(tài)時(shí)異常");
            e.printStackTrace();
        }
        log.info("支付回調(diào)通知微信的xml【" + resXml + "】");
        log.info("======================= 微信支付回調(diào)結(jié)束 =======================");
    }

驗(yàn)簽

/**
     * 驗(yàn)證簽名字符串
     *
     * @param map           需要簽名的數(shù)據(jù)
     * @param key           微信商戶支付密鑰
     * @param input_charset 編碼格式
     * @return 簽名結(jié)果
     */
    public static boolean verify(Map<String, String> map, String key, String input_charset) {

        //驗(yàn)證簽名是否正確
        //回調(diào)驗(yàn)簽時(shí)需要去除sign和空值參數(shù)
        Map<String, String> validParams = this.paraFilter(map);
        //把參數(shù)按規(guī)則排序拼接
        String prestr = this.createLinkString(validParams);

        String sign = map.get("sign");
        String mysign = this.sign(prestr, key, input_charset).toUpperCase();

        log.info("返回簽名：" + sign + "  生成簽名：" + mysign);

        if (mysign.equals(sign)) {
            log.info("支付回調(diào)返回?cái)?shù)據(jù)簽名驗(yàn)證通過!!!");
            return true;
        } else {
            return false;
        }
    }

去除無效值

/**
     * 除去數(shù)組中的空值和簽名參數(shù)
     *
     * @param sArray 簽名參數(shù)組
     * @return 去掉空值與簽名參數(shù)后的新簽名參數(shù)組
     */
    public static Map<String, String> paraFilter(Map<String, String> sArray) {
        Map<String, String> result = new HashMap<String, String>();
        if (sArray == null || sArray.size() <= 0) {
            return result;
        }
        for (String key : sArray.keySet()) {
            String value = sArray.get(key);
            if (value == null || value.equals("") || key.equalsIgnoreCase("sign")
                    || key.equalsIgnoreCase("sign_type")) {
                continue;
            }
            result.put(key, value);
        }
        return result;
    }

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