支付宝退款demo

<dependency>
    <groupId>com.alipay.sdk</groupId>
    <artifactId>alipay-sdk-java</artifactId>
    <version>4.7.12.ALL</version>
</dependency>

public class AliPayConfig {
public static String APP_ID="替换为自己的";
public static String APP_PRIVATE_KEY = "替换为自己的";// 私钥

private static String requestUrl = "https://openapi.alipay.com/gateway.do";//支付宝请求退款的网关地址

/**
* 该公钥对应开放平台密钥的支付宝公钥，*/
public static String ALIPAY_PUBLIC_KEY="替换为自己的";//支付宝公钥
public static String CHARSET = "utf-8";//字符编码
public static String SIGN_TYPE = "RSA";//签名方式
}

 public boolean refund22(String orderId, String tradeNo, BigDecimal refundAmount ) {
        //实例化客户端
        AlipayClient alipayClient = new DefaultAlipayClient("网关 https://openapi.alipay.com/gateway.do",
                "appId",
                "私钥",
                "数据类型 json",
　　　　　　　　　　"utf-8",
                "公钥",
                "RSA2");
        AlipayTradeRefundRequest request = new AlipayTradeRefundRequest();
        Map params = new HashMap();
        if (orderId!=null&&!"".equals(orderId))params.put("out_trade_no",orderId);//商家订单号
        if (tradeNo!=null&&!"".equals(tradeNo))params.put("trade_no",tradeNo);//支付宝交易号(一般必选)
        //请求退款的金额
        params.put("refund_amount",refundAmount);
        //该参数支持部分退款(如果不加则进行全额退款,可用随机数去生成)
        params.put("out_request_no","BZ35581R88001");
        //可加参数
        String paramsJsonStr = JSONObject.toJSONString(params);
        request.setBizContent(paramsJsonStr);
        try {
            AlipayTradeRefundResponse response = alipayClient.execute(request);
            return response.isSuccess();
        }catch (Exception e){
            String json = e.getMessage();
            json = json.substring(json.indexOf("{"),json.indexOf("}")+1);
            Map retMap = JSONObject.parseObject(json);
            return "10000".equals(retMap.get("code").toString());
        }
    }