lengshanwlj / paypal-java-sdk

Java SDK for PayPal RESTful APIs

PayPal REST API Java SDK

This repository contains Java SDK and samples for REST API. For PayPal mobile(Android) SDK, please go to PayPal Android SDK

Prerequisites:

• Java JDK-1.5 or higher
• Apache Maven 3 or higher
• Please refer http://maven.apache.org/guides/getting-started/maven-in-five-minutes.html for any help in Maven.

SDK Integration:

For Maven Users:

• Create a new maven application.

• Add dependency to sdk in your application's pom.xml as below.

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

To make an API call:

• Import stub classes into your code. For example,

  import com.paypal.api.payments.*

• Copy the configuration file sdk_config.properties in rest-api-sample/src/test/resources folder to your application src/main/resources. And load it as a classloader resource,

  InputStream is = PaymentWithCreditCardServlet.class.getResourceAsStream("/sdk_config.properties");

• Or load config file from any custom location using absolute path with the below method calls as required,

  OAuthTokenCredential tokenCredential = Payment.initConfig(new File("../sdk_config.properties"));
  					Or
  OAuthTokenCredential tokenCredential = Payment.initConfig(new InputStream(new File("../sdk_config.properties")));
  					Or
  OAuthTokenCredential tokenCredential = Payment.initConfig(new Properties().load(new InputStream(new File("../sdk_config.properties"))));

• Create accesstoken from the above OAuthTokenCredential

  String accessToken = tokenCredential.getAccessToken()

• Alternatively, create accesstoken from clientID and clientSecret using OAuthTokenCredential

  String accessToken = new OAuthTokenCredential(clientID, clientSecret).getAccessToken();

• Depending on the context of API calls, calling method may be static or non-static (For example, most GET http methods are created as static methods within the resource). In all API calls, we need to pass accessToken created above as argument as shown below,

  • If it is static, invoke it as a class method as like

    Payment.get(accessToken, paymentID);

  • If it is non-static, invoke it using resource object as like below. The API call takes a APIContext object in the place of AccessToken, APIContext object encapsulates Access Token and Request ID (used for idempotency).

    APIContext apiContext = new APIContext(accessToken);
    		     (OR)
    APIContext apiContext = new APIContext(accessToken, requestId);
    Payment payment = new Payment();
    payment.setIntent("sale");
    ...		
    payment.create(apiContext);

• Future Payments sample is available here for executing future payments for a customer who has granted consent on a mobile device.

• For Invoicing, check out the samples to see how you can use the node sdk to create, send and manage invoices.

Running Samples

SDK Configuration:

The SDK uses Java properties format configuration file. Sample of this file is at

rest-api-sample/src/test/resources/. You can use the sdk_config.properties configuration file to configure

• HTTP connection parameters.

• Service configuration.

• Credentials

OpenID Connect Integration

• Redirect your buyer to Authorization.getRedirectUrl(redirectURI, scope, configurationMap); to obtain authorization.
• Capture the authorization code that is available as a query parameter (code) in the redirect url
• Exchange the authorization code for a access token, refresh token, id token combo

    Map<String, String> configurationMap = new HashMap<String, String>();
    configurationMap.put(Constants.CLIENT_ID, "...");
    configurationMap.put(Constants.CLIENT_SECRET, "...");
    configurationMap.put(Constants.ENDPOINT, "https://api.paypal.com/");
    APIContext apiContext = new APIContext();
    apiContext.setConfigurationMap(configurationMap);
    ...
    CreateFromAuthorizationCodeParameters param = new CreateFromAuthorizationCodeParameters();
    param.setCode(code);
    Tokeninfo info = Tokeninfo.createFromAuthorizationCode(apiContext, param);
    String accessToken = info.getAccessToken();

• The access token is valid for a predefined duration and can be used for seamless XO or for retrieving user information

    Map<String, String> configurationMap = new HashMap<String, String>();
    configurationMap.put(Constants.CLIENT_ID, "...");
    configurationMap.put(Constants.CLIENT_SECRET, "...");
    configurationMap.put(Constants.ENDPOINT, "https://api.paypal.com/");
    APIContext apiContext = new APIContext();
    apiContext.setConfigurationMap(configurationMap);
    ...
    Tokeninfo info = new Tokeninfo();
    info.setRefreshToken("refreshToken");
    UserinfoParameters param = new UserinfoParameters();
    param.setAccessToken(info.getAccessToken());
    Userinfo userInfo = Userinfo.userinfo(apiContext, param);

• If the access token has expired, you can obtain a new access token using the refresh token from the 3'rd step.

    Map<String, String> configurationMap = new HashMap<String, String>();
    configurationMap.put(Constants.CLIENT_ID, "...");
    configurationMap.put(Constants.CLIENT_SECRET, "...");
    configurationMap.put(Constants.ENDPOINT, "https://api.paypal.com/");
    APIContext apiContext = new APIContext();
    apiContext.setConfigurationMap(configurationMap);
    ...
    CreateFromRefreshTokenParameters param = new CreateFromRefreshTokenParameters();
    param.setScope("openid"); // Optional
    Tokeninfo info = new Tokeninfo // Create Token info object; setting the refresh token
    info.setRefreshToken("refreshToken");

    info.createFromRefreshToken(apiContext, param);