Java实现微信支付

<dependency>
  <groupId>com.github.wechatpay-apiv3</groupId>
  <artifactId>wechatpay-java</artifactId>
  <version>0.2.10</version>
</dependency>

import com.wechat.pay.java.core.Config;
import com.wechat.pay.java.core.RSAConfig;
import com.wechat.pay.java.service.payments.jsapi.JsapiService;
import com.wechat.pay.java.service.payments.jsapi.model.Amount;
import com.wechat.pay.java.service.payments.jsapi.model.Payer;
import com.wechat.pay.java.service.payments.jsapi.model.PrepayRequest;
import com.wechat.pay.java.service.payments.jsapi.model.PrepayResponse;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
@Component
public class WeiXinPay {
    //@Value("${weixin.appId}")
    private String weixinAppId;
    /** 商户号 */
    public static String merchantId = "";
    /** 商户API私钥路径 */
    public static String privateKeyPath = "";
    /** 商户证书序列号 例如-证书序列号：54776TTTF8F77EXXX3641FAB5F940FII11C65347*/
    public static String merchantSerialNumber = "";
    /** 微信支付平台证书路径 例如：wechatpay_3A4AF69999DF01F39BB08C21C1C29B6AA17C074N.pem*/
    public static String wechatPayCertificatePath = "";
    /** 微信支付 APIv3 密钥 */
    public static String apiV3Key = "";
    public String createPreparePay() {
        Config config =
                new RSAConfig.Builder()
                        //商户ID
                        .merchantId(merchantId)
                        //商户私钥文件(apiclient_key.pem)路径
                        .privateKeyFromPath(privateKeyPath)
                        //商户证书序列号 例如-证书序列号：54776TTTF8F77EXXX3641FAB5F940FII11C65347
                        .merchantSerialNumber(merchantSerialNumber)
                        //微信支付平台证书文件路径 例如：wechatpay_3A4AF69999DF01F39BB08C21C1C29B6AA17C074N.pem
                        .wechatPayCertificatesFromPath(wechatPayCertificatePath)
                        .build();
        JsapiService service = new JsapiService.Builder().config(config).build();
        PrepayRequest request = new PrepayRequest();
        Amount amount = new Amount();
        amount.setTotal(100);
        request.setAmount(amount);
        request.setAppid("wxa9d9651ae******");
        request.setMchid("190000****");
        request.setDescription("测试商品标题");
        request.setNotifyUrl("https://notify_url");
        request.setOutTradeNo("out_trade_no_001");
        Payer payer = new Payer();
        payer.setOpenid("oLTPCuN5a-nBD4rAL_fa********");
        request.setPayer(payer);
        PrepayResponse response = service.prepay(request);
        System.out.println(response.getPrepayId());
        return "";
    }
}