> For the complete documentation index, see [llms.txt](https://docs.ecommerce.seb.ee/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ecommerce.seb.ee/integration/api-client-sdk/quickstarts/java.md). # Java Set up the Java SDK, initiate a sandbox payment, and configure the client. ## Prerequisites * Java 11 or later, Maven or Gradle. * Sandbox API credentials: **client ID** and **client secret**, plus your **participant ID** and **shop agreement ID**. Register and generate these yourself at the **Merchant Portal**: . * The SDK **distribution ZIP**, downloaded from this documentation site. ## Install Download `egw-java-sdk-.zip` and its matching `.sha256` file, verify the download, then unzip it and install the JARs into your local Maven repository: ```bash sha256sum -c egw-java-sdk-.zip.sha256 unzip egw-java-sdk-.zip -d egw-sdk cd egw-sdk mvn install:install-file \ -Dfile=egw-java-core-.jar \ -DpomFile=egw-java-core-.pom \ -Dsources=egw-java-core--sources.jar ``` Installing with `-DpomFile` is what makes the SDK's own dependencies (Jackson, Nimbus JOSE+JWT, SLF4J API) resolve automatically. Without it you must declare each of them yourself. Then depend on it as normal: ```xml com.tieto.banking.egw egw-java-core ``` For a shared team setup, deploy the same artifact once to your organization's internal repository (`mvn deploy:deploy-file`) instead of having every developer install it locally. ## Create a client and make your first call In this example, the credentials are retrieved from environment variables — never commit or log real credentials. ```java import com.tieto.banking.egw.merchantapi.sdk.application.EgwClient; import com.tieto.banking.egw.merchantapi.sdk.application.bootstrap.DefaultEgwClientFactory; import com.tieto.banking.egw.merchantapi.sdk.application.dto.CitPaymentChannel; import com.tieto.banking.egw.merchantapi.sdk.application.dto.InitiatePaymentResponse; import java.net.URI; try (EgwClient client = new DefaultEgwClientFactory() .connectingTo(URI.create("https://sandbox.api.ecommerce.sebgroup.com")) .authorizingAs(System.getenv("EGW_CLIENT_ID"), System.getenv("EGW_CLIENT_SECRET")) .createEgwClient()) { InitiatePaymentResponse response = client.payments().initiateCitPayment(b -> b .channel(CitPaymentChannel.BROWSER) .instructedAmount(a -> a.amount("100.00").currency("EUR")) .orderNumber("ORD-001") .participantId(System.getenv("EGW_PARTICIPANT_ID")) .shopAgreementId(System.getenv("EGW_SHOP_AGREEMENT_ID")) .shopRedirectUrl("https://shop.example.com/return") .description("First sandbox payment")); System.out.println("Payment created: " + response.getPaymentId()); } ``` What happened automatically: the factory derived the OAuth token endpoint and the JWE key endpoint from the base URL; the client fetched and cached an OAuth 2.0 access token before the call; a unique `X-Request-ID` header was generated for the request. `EgwClient` is immutable and safe to share; create it once and reuse it (the OAuth token cache is thread-safe). `close()` only matters if you enabled the webhook listener. Amounts are **decimal strings** (`"100.00"`), currencies ISO 4217 alpha-3. For test cards and magic values, see [Sandbox test data](/guides/sandbox.md). ## Customizing the client The factory accepts optional replacements before `createEgwClient()`: * `connectingWith(ApiClient)` — you may supply your own HTTP client implementation. * `loggingWith(EgwLogger)` — plug in your logging; the default logger is silent. See the warning in [Security mechanics](/integration/api-client-sdk/guides/security-mechanics.md#logging) before enabling logging in production. * `listeningAt(URI)` / `listeningWith(ApiServer)` — enable the webhook listener; see [Security mechanics](/integration/api-client-sdk/guides/security-mechanics.md#webhook-notifications). Infrastructure adapters (HTTP, serializer, encrypter) can also be replaced application-wide via Java `ServiceLoader` providers (`ApiClientProvider`, `SerializerProvider`, `DataEncrypterProvider`, `EgwLoggerProvider` in `…bootstrap.spi`). See [Overriding SDK adapters](/integration/api-client-sdk/guides/overriding-sdk-adapters.md) for a full walkthrough. ## Next steps * [Security mechanics](/integration/api-client-sdk/guides/security-mechanics.md) — card encryption for card checkout sessions, webhooks. * [Error handling](/integration/api-client-sdk/guides/error-handling.md) — the exception hierarchy and retry guidance. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. 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