Java后端调用微信支付和支付宝支付的详细步骤

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

import com.github.wxpay.sdk.WXPay;
import com.github.wxpay.sdk.WXPayConfig;
import com.github.wxpay.sdk.WXPayConstants;
import com.github.wxpay.sdk.WXPayUtil;

import java.util.HashMap;
import java.util.Map;

public class WechatPayExample {

    public static void main(String[] args) throws Exception {
        // 实现 WXPayConfig 接口
        WXPayConfig config = new WXPayConfig() {
            @Override
            public String getAppID() {
                return "your_app_id";
            }

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

            @Override
            public String getKey() {
                return "your_api_key";
            }

            @Override
            public InputStream getCertStream() {
                // 加载商户证书
                return WechatPayExample.class.getResourceAsStream("/apiclient_cert.p12");
            }

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

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

        WXPay wxpay = new WXPay(config, WXPayConstants.SignType.MD5);

        // 组装请求参数
        Map<String, String> data = new HashMap<>();
        data.put("body", "商品描述");
        data.put("out_trade_no", "20250225001");
        data.put("total_fee", "1");
        data.put("spbill_create_ip", "127.0.0.1");
        data.put("notify_url", "https://yourdomain.com/notify");
        data.put("trade_type", "NATIVE");

        // 调用统一下单接口
        Map<String, String> resp = wxpay.unifiedOrder(data);
        System.out.println(resp);

        if ("SUCCESS".equals(resp.get("return_code")) && "SUCCESS".equals(resp.get("result_code"))) {
            String codeUrl = resp.get("code_url");
            System.out.println("生成的二维码链接: " + codeUrl);
        }
    }
}

<dependency>
    <groupId>com.alipay.sdk</groupId>
    <artifactId>alipay-sdk-java</artifactId>
    <version>4.10.115.ALL</version>
</dependency>

import com.alipay.api.AlipayApiException;
import com.alipay.api.AlipayClient;
import com.alipay.api.DefaultAlipayClient;
import com.alipay.api.request.AlipayTradePagePayRequest;

public class AlipayExample {

    public static void main(String[] args) {
        // 支付宝网关
        String gatewayUrl = "https://openapi.alipay.com/gateway.do";
        // 应用 ID
        String appId = "your_app_id";
        // 应用私钥
        String privateKey = "your_private_key";
        // 支付宝公钥
        String alipayPublicKey = "your_alipay_public_key";
        // 字符编码格式
        String charset = "UTF-8";
        // 签名方式
        String signType = "RSA2";
        // 支付成功回调地址
        String returnUrl = "https://yourdomain.com/return";
        // 支付结果通知地址
        String notifyUrl = "https://yourdomain.com/notify";

        // 创建 AlipayClient 对象
        AlipayClient alipayClient = new DefaultAlipayClient(gatewayUrl, appId, privateKey, "json", charset, alipayPublicKey, signType);

        // 创建 AlipayTradePagePayRequest 对象
        AlipayTradePagePayRequest alipayRequest = new AlipayTradePagePayRequest();
        alipayRequest.setReturnUrl(returnUrl);
        alipayRequest.setNotifyUrl(notifyUrl);

        // 组装请求参数
        alipayRequest.setBizContent("{\"out_trade_no\":\"20250225002\"," +
                "\"total_amount\":\"0.01\"," +
                "\"subject\":\"商品名称\"," +
                "\"product_code\":\"FAST_INSTANT_TRADE_PAY\"}");

        try {
            // 调用支付接口
            String result = alipayClient.pageExecute(alipayRequest).getBody();
            System.out.println(result);
        } catch (AlipayApiException e) {
            e.printStackTrace();
        }
    }
}