1.註冊開發者中心應用 登入點選沙箱服務

https://open.alipay.com/platform/developerIndex.htm

2.建立沙箱應用獲取APPID和支付寶閘道器地址(建立設定金鑰這裡就不說明了)，將公共金鑰和私密儲存到本地。

3.建立專案結構，設定配置檔案

1.下載支付寶SDK檔案jar包，講jar包匯入到專案內

2.編寫配置資訊和Java檔案

/********************************************************************************************************************************************************************************************/

* 應用啟動載入檔案*/
@Component
public class AlipayConfig implements ApplicationListener {
    //儲存載入配置引數
    private static Map<String, String> aliPropertiesMap = new HashMap<String, String>();

    /*獲取配置引數值*/
    public static String getKey(String key) {
        return aliPropertiesMap.get(key);
    }

    /*監聽啟動完成，執行配置載入到aliPropertiesMap*/
 

    public void onApplicationEvent(ApplicationEvent event) {
        if (event instanceof ApplicationReadyEvent) {
            this.init(aliPropertiesMap);//應用啟動載入
        }
    }

    /*初始化載入aliPropertiesMap*/
    public void init(Map<String, String> map) {
        // 獲得PathMatchingResourcePatternResolver物件
 

        PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
        try {
            //載入resource檔案(也可以載入resources)
            Resource resources = resolver.getResource("classpath:/alipay.properties");
            PropertiesFactoryBean config = new PropertiesFactoryBean();
            config.setLocation(resources);
            config.afterPropertiesSet();
            Properties prop = config.getObject();
            //迴圈遍歷所有得鍵值對並且存入集合
            for (String key : prop.stringPropertyNames()) {
                map.put(key, (String) prop.get(key));
            }
        } catch (Exception e) {
            new Exception("配置檔案載入失敗");
        }
    }
}

/********************************************************************************************************************************************************************************************/

4.建立支付工具類

public class PayUtil {


    /**
     * @param outTradeNo  商戶訂單號，商戶網站訂單系統中唯一訂單號，必填   對應繳費記錄的orderNo
     * @param totalAmount 付款金額，必填
     * @param subject     主題
     * @param body        商品描述，可空
     * @return
     */
    public static String alipay(AlipayBean alipayBean) {

        //1、獲得初始化的AlipayClient
        AlipayClient alipayClient = new DefaultAlipayClient(
                AlipayConfig.getKey("gatewayUrl"),//支付寶閘道器
                AlipayConfig.getKey("app_id"),//appid
                AlipayConfig.getKey("merchant_private_key"),//商戶私鑰
                "json",
                AlipayConfig.getKey("charset"),//字元編碼格式
                AlipayConfig.getKey("alipay_public_key"),//支付寶公鑰
                AlipayConfig.getKey("sign_type")//簽名方式
        );


        //設定請求引數
        AlipayTradePagePayRequest alipayRequest = new AlipayTradePagePayRequest();
        alipayRequest.setReturnUrl(AlipayConfig.getKey("return_url"));
        alipayRequest.setNotifyUrl(AlipayConfig.getKey("notify_url"));
        try {
            alipayRequest.setBizContent(JSON.toJSONString(alipayBean));

            //請求
            String result = alipayClient.pageExecute(alipayRequest).getBody();
            System.out.println("*********************\n返回結果為：" + result);
            return result;
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 支付寶退款介面
     *
     * @param outTradeNo
     * @param tradeNo
     * @param refundAmount
     * @param refundReason
     * @param out_request_no 標識一次退款請求，同一筆交易多次退款需要保證唯一，如需部分退款，則此引數必傳
     * @return
     */
    public static String aliRefund(AlipayBean alipayBean) {

        //1、獲得初始化的AlipayClient
        AlipayClient alipayClient = new DefaultAlipayClient(
                AlipayConfig.getKey("gatewayUrl"),//支付寶閘道器
                AlipayConfig.getKey("app_id"),//appid
                AlipayConfig.getKey("merchant_private_key"),//商戶私鑰
                "json",
                AlipayConfig.getKey("charset"),//字元編碼格式
                AlipayConfig.getKey("alipay_public_key"),//支付寶公鑰
                AlipayConfig.getKey("sign_type")//簽名方式
        );

        //設定請求引數
        AlipayTradeRefundRequest alipayRequest = new AlipayTradeRefundRequest();
        alipayRequest.setReturnUrl(AlipayConfig.getKey("return_url"));
        alipayRequest.setNotifyUrl(AlipayConfig.getKey("notify_url"));
        try {
            alipayRequest.setBizContent(JSON.toJSONString(alipayBean));

            //請求
            String result= alipayClient.execute(alipayRequest).getBody();
            System.out.println("*********************\n返回結果為：" + result);
            return result;
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 支付寶的驗籤方法
     *
     * @param req
     * @return
     */
    public static boolean checkSign(HttpServletRequest req) {
        Map<String, String[]> requestMap = req.getParameterMap();
        Map<String, String> paramsMap = new HashMap<>();
        requestMap.forEach((key, values) -> {
            String strs = "";
            for (String value : values) {
                strs = strs + value;
            }
            System.out.println(("key值為" + key + "value為：" + strs));
            paramsMap.put(key, strs);
        });

        //呼叫SDK驗證簽名
        try {
            return AlipaySignature.rsaCheckV1(paramsMap, AlipayConfig.getKey("alipay_public_key"), AlipayConfig.getKey("charset"), AlipayConfig.getKey("sign_type"));
        } catch (AlipayApiException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            System.out.println("*********************驗籤失敗********************");
            return false;
        }
    }

5.建立Controller，dao和service

6.建立測試html，執行專案訪問測試。

over......