最详细的 paypal 支付接口开发--Java版

做全球性的支付，选用paypal！为什么选择paypal？ 因为paypal是目前全球最大的在线支付工具，就像国内的支付宝一样，是一个基于买卖双方的第三方平台。买家只需知道你的paypal账号，即可在线直接把钱汇入你的账户，即时到账，简单方便快捷。

在集成paypal支付接口之前，首先要有一系列的准备，开发者账号啊、sdk、测试环境等等先要有，然后再码代码。集成的步骤如下：

一、环境准备

• 注册paypal账号

• 注册paypal开发者账号

• 创建两个测试用户

• 创建应用，生成用于测试的clientID 和 密钥

二、代码集成

• springboot环境

• pom引进paypal-sdk的jar包

• 码代码

• 测试

• 后言

现在开始

• 注册paypal账号

（1）在浏览器输入“https://www.paypal.com” 跳转到如下界面，点击右上角的注册

（2）选择，”创建商家用户”，根据要求填写信息，一分钟的事，注册完得去邮箱激活

• 注册paypal开发者账号

  （1）在浏览器输入“https://developer.paypal.com”，点击右上角的“Log into Dashboard”，用上一步创建好的账号登录

• 创建两个测试用户

（1）登录成功后，在左边的导航栏中点击 Sandbox 下的 Accounts

（2）进入Acccouts界面后，可以看到系统有两个已经生成好的测试账号，但是我们不要用系统给的测试账号，很卡的，自己创建两个

（3）点击右上角的“Create Account”，创建测试用户

<1> 先创建一个“ PERSONAL”类型的用户，国家一定要选“China”，账户余额自己填写

<2> 接着创建一个“BUSINESS”类型的用户，国家一定要选“China”，账户余额自己填写

<3>创建好之后可以点击测试账号下的”Profile“，可以查看信息，如果没加载出来，刷新

<4>用测试账号登录测试网站查看，注意！这跟paypal官网不同！不是同一个地址，在浏览器输入：https://www.sandbox.paypal.com 在这里登陆测试账户

• 创建应用，生成用于测试的clientID 和 密钥

  （1）点击左边导航栏Dashboard下的My Apps & Credentials，创建一个Live账号，下图是我已经创建好的

（2）然后再到下边创建App

这是我创建好的“Test”App

（3）点击刚刚创建好的App“Test”，注意看到”ClientID“ 和”Secret“(Secret如果没显示，点击下面的show就会看到，点击后show变为hide)

• springboot环境搭建

  （1）新建几个包，和目录，项目结构如下

• pom引进paypal-sdk的jar包

  （1）pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.masasdani</groupId>
  <artifactId>paypal-springboot</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <name>paypal-springboot</name>

  <repositories>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>http://repo.spring.io/libs-milestone</url>
        </repository>
        <repository>
            <id>jcenter-snapshots</id>
            <name>jcenter</name>
            <url>https://jcenter.bintray.com/</url>
        </repository>
    </repositories>

    <pluginRepositories>
        <pluginRepository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>http://repo.spring.io/libs-milestone</url>
        </pluginRepository>
    </pluginRepositories>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.3.0.RELEASE</version>
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.7</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>com.paypal.sdk</groupId>
            <artifactId>rest-api-sdk</artifactId>
            <version>1.4.2</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

• 码代码

  （1）Application.java

package com.masasdani.paypal;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;

@EnableAutoConfiguration
@Configuration
@ComponentScan
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

（2）PaypalConfig.java

package com.masasdani.paypal.config;

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

import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.paypal.base.rest.APIContext;
import com.paypal.base.rest.OAuthTokenCredential;
import com.paypal.base.rest.PayPalRESTException;

@Configuration
public class PaypalConfig {

    @Value("${paypal.client.app}")
    private String clientId;
    @Value("${paypal.client.secret}")
    private String clientSecret;
    @Value("${paypal.mode}")
    private String mode;

    @Bean
    public Map<String, String> paypalSdkConfig(){
        Map<String, String> sdkConfig = new HashMap<>();
        sdkConfig.put("mode", mode);
        return sdkConfig;
    }

    @Bean
    public OAuthTokenCredential authTokenCredential(){
        return new OAuthTokenCredential(clientId, clientSecret, paypalSdkConfig());
    }

    @Bean
    public APIContext apiContext() throws PayPalRESTException{
        APIContext apiContext = new APIContext(authTokenCredential().getAccessToken());
        apiContext.setConfigurationMap(paypalSdkConfig());
        return apiContext;
    }
}

（3）PaypalPaymentIntent.java

package com.masasdani.paypal.config;

public enum PaypalPaymentIntent {

    sale, authorize, order

}

（4）PaypalPaymentMethod.java

package com.masasdani.paypal.config;

public enum PaypalPaymentMethod {

    credit_card, paypal

}

（5）PaymentController.java

package com.masasdani.paypal.controller;

import javax.servlet.http.HttpServletRequest;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;

import com.masasdani.paypal.config.PaypalPaymentIntent;
import com.masasdani.paypal.config.PaypalPaymentMethod;
import com.masasdani.paypal.service.PaypalService;
import com.masasdani.paypal.util.URLUtils;
import com.paypal.api.payments.Links;
import com.paypal.api.payments.Payment;
import com.paypal.base.rest.PayPalRESTException;

@Controller
@RequestMapping("/")
public class PaymentController {

    public static final String PAYPAL_SUCCESS_URL = "pay/success";
    public static final String PAYPAL_CANCEL_URL = "pay/cancel";

    private Logger log = LoggerFactory.getLogger(getClass());

    @Autowired
    private PaypalService paypalService;

    @RequestMapping(method = RequestMethod.GET)
    public String index(){
        return "index";
    }

    @RequestMapping(method = RequestMethod.POST, value = "pay")
    public String pay(HttpServletRequest request){
        String cancelUrl = URLUtils.getBaseURl(request) + "/" + PAYPAL_CANCEL_URL;
        String successUrl = URLUtils.getBaseURl(request) + "/" + PAYPAL_SUCCESS_URL;
        try {
            Payment payment = paypalService.createPayment(
                    500.00,
                    "USD",
                    PaypalPaymentMethod.paypal,
                    PaypalPaymentIntent.sale,
                    "payment description",
                    cancelUrl,
                    successUrl);
            for(Links links : payment.getLinks()){
                if(links.getRel().equals("approval_url")){
                    return "redirect:" + links.getHref();
                }
            }
        } catch (PayPalRESTException e) {
            log.error(e.getMessage());
        }
        return "redirect:/";
    }

    @RequestMapping(method = RequestMethod.GET, value = PAYPAL_CANCEL_URL)
    public String cancelPay(){
        return "cancel";
    }

    @RequestMapping(method = RequestMethod.GET, value = PAYPAL_SUCCESS_URL)
    public String successPay(@RequestParam("paymentId") String paymentId, @RequestParam("PayerID") String payerId){
        try {
            Payment payment = paypalService.executePayment(paymentId, payerId);
            if(payment.getState().equals("approved")){
                return "success";
            }
        } catch (PayPalRESTException e) {
            log.error(e.getMessage());
        }
        return "redirect:/";
    }

}

（6）PaypalService.java

package com.masasdani.paypal.service;

import java.util.ArrayList;
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.masasdani.paypal.config.PaypalPaymentIntent;
import com.masasdani.paypal.config.PaypalPaymentMethod;
import com.paypal.api.payments.Amount;
import com.paypal.api.payments.Payer;
import com.paypal.api.payments.Payment;
import com.paypal.api.payments.PaymentExecution;
import com.paypal.api.payments.RedirectUrls;
import com.paypal.api.payments.Transaction;
import com.paypal.base.rest.APIContext;
import com.paypal.base.rest.PayPalRESTException;

@Service
public class PaypalService {

    @Autowired
    private APIContext apiContext;

    public Payment createPayment(
            Double total,
            String currency,
            PaypalPaymentMethod method,
            PaypalPaymentIntent intent,
            String description,
            String cancelUrl,
            String successUrl) throws PayPalRESTException{
        Amount amount = new Amount();
        amount.setCurrency(currency);
        amount.setTotal(String.format("%.2f", total));

        Transaction transaction = new Transaction();
        transaction.setDescription(description);
        transaction.setAmount(amount);

        List<Transaction> transactions = new ArrayList<>();
        transactions.add(transaction);

        Payer payer = new Payer();
        payer.setPaymentMethod(method.toString());

        Payment payment = new Payment();
        payment.setIntent(intent.toString());
        payment.setPayer(payer);
        payment.setTransactions(transactions);
        RedirectUrls redirectUrls = new RedirectUrls();
        redirectUrls.setCancelUrl(cancelUrl);
        redirectUrls.setReturnUrl(successUrl);
        payment.setRedirectUrls(redirectUrls);

        return payment.create(apiContext);
    }

    public Payment executePayment(String paymentId, String payerId) throws PayPalRESTException{
        Payment payment = new Payment();
        payment.setId(paymentId);
        PaymentExecution paymentExecute = new PaymentExecution();
        paymentExecute.setPayerId(payerId);
        return payment.execute(apiContext, paymentExecute);
    }
}

（7）URLUtils.java

package com.masasdani.paypal.util;

import javax.servlet.http.HttpServletRequest;

public class URLUtils {

    public static String getBaseURl(HttpServletRequest request) {
        String scheme = request.getScheme();
        String serverName = request.getServerName();
        int serverPort = request.getServerPort();
        String contextPath = request.getContextPath();
        StringBuffer url =  new StringBuffer();
        url.append(scheme).append("://").append(serverName);
        if ((serverPort != 80) && (serverPort != 443)) {
            url.append(":").append(serverPort);
        }
        url.append(contextPath);
        if(url.toString().endsWith("/")){
            url.append("/");
        }
        return url.toString();
    }

}

（8）cancel.html

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Insert title here</title>
</head>
<body>
    <h1>Canceled by user</h1>
</body>
</html>

（9）index.html

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Insert title here</title>
</head>
<body>
<form method="post" th:action="@{/pay}">
    <button type="submit"><img src="data:images/paypal.jpg" width="100px;" height="30px;"/></button>
</form>
</body>
</html>

（10）success.html

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Insert title here</title>
</head>
<body>
    <h1>Payment Success</h1>
</body>
</html>

（11）最重要的！application.properties,paypal.client.app是App的CilentID， paypal.client.secret是Secret

server.port: 8088
spring.thymeleaf.cache=false

paypal.mode=sandbox
paypal.client.app=AeVqmY_pxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxKYniPwzfL1jGR
paypal.client.secret=ELibZhExxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxUsWOA

• 测试

  （1）启动项目

（2）在浏览器输入localhost:8088

（3）点击paypal后，会跳到paypal的登录界面，登录测试账号（PRESONAL）后点击继续即可扣费，扣500$(具体数额可在controller中自定义)

Payment payment = paypalService.createPayment(
                    500.00,
                    "USD",
                    PaypalPaymentMethod.paypal,
                    PaypalPaymentIntent.sale,
                    "payment description",
                    cancelUrl,
                    successUrl);

（4）到https://www.sandbox.paypal.com 登录测试账号看看余额有没有变化

http://blog.csdn.net/change_on/article/details/73881791