在Java中使用spring boot实现Paypal自适应支付

在Java中使用Spring Boot实现Paypal自适应支付，可以通过以下步骤完成：

首先，确保已经安装了Java开发环境和Spring Boot框架。
创建一个Spring Boot项目，并添加所需的依赖项。在项目的pom.xml文件中添加以下依赖：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

<dependency>
    <groupId>com.paypal.sdk</groupId>
    <artifactId>rest-api-sdk</artifactId>
    <version>1.14.0</version>
</dependency>

创建一个Controller类，用于处理支付请求和回调。在该类中，可以使用Paypal的Java SDK来实现自适应支付功能。

import com.paypal.api.payments.*;
import com.paypal.base.rest.APIContext;
import com.paypal.base.rest.PayPalRESTException;
import org.springframework.web.bind.annotation.*;

@RestController
@RequestMapping("/paypal")
public class PaypalController {

    @PostMapping("/payment")
    public String createPayment() {
        // 创建支付对象
        Payment payment = new Payment();
        payment.setIntent("sale");
        payment.setPayer(getPayer());
        payment.setTransactions(getTransactions());
        payment.setRedirectUrls(getRedirectUrls());

        try {
            // 创建支付并获取支付链接
            APIContext apiContext = new APIContext("YOUR_CLIENT_ID", "YOUR_CLIENT_SECRET", "sandbox");
            Payment createdPayment = payment.create(apiContext);
            return createdPayment.getLinks().get(1).getHref();
        } catch (PayPalRESTException e) {
            e.printStackTrace();
            return "Error occurred while creating payment!";
        }
    }

    @GetMapping("/payment/execute")
    public String executePayment(@RequestParam("paymentId") String paymentId, @RequestParam("PayerID") String payerId) {
        try {
            // 执行支付
            APIContext apiContext = new APIContext("YOUR_CLIENT_ID", "YOUR_CLIENT_SECRET", "sandbox");
            Payment payment = new Payment();
            payment.setId(paymentId);
            PaymentExecution paymentExecution = new PaymentExecution();
            paymentExecution.setPayerId(payerId);
            Payment executedPayment = payment.execute(apiContext, paymentExecution);
            return "Payment successfully executed!";
        } catch (PayPalRESTException e) {
            e.printStackTrace();
            return "Error occurred while executing payment!";
        }
    }

    private Payer getPayer() {
        Payer payer = new Payer();
        payer.setPaymentMethod("paypal");
        return payer;
    }

    private List<Transaction> getTransactions() {
        Transaction transaction = new Transaction();
        transaction.setAmount(getAmount());
        transaction.setDescription("Payment description");
        List<Transaction> transactions = new ArrayList<>();
        transactions.add(transaction);
        return transactions;
    }

    private Amount getAmount() {
        Amount amount = new Amount();
        amount.setCurrency("USD");
        amount.setTotal("10.00");
        return amount;
    }

    private RedirectUrls getRedirectUrls() {
        RedirectUrls redirectUrls = new RedirectUrls();
        redirectUrls.setReturnUrl("http://your-website.com/paypal/payment/execute");
        redirectUrls.setCancelUrl("http://your-website.com/paypal/payment/cancel");
        return redirectUrls;
    }
}