Getting Started with the eBay SDK for Java: Installation to First API CallThis guide walks you through everything needed to get the eBay SDK for Java set up and make your first API call. It covers prerequisites, installation options, authentication, configuration, making requests, handling responses, and basic troubleshooting. Examples use Java 11+ and the official eBay REST APIs.
What you’ll need
- Java 11 or newer installed and configured (JDK).
- Maven or Gradle for dependency management.
- An eBay developer account (create one at developer.ebay.com).
- An application (App ID / Client ID) and Client Secret from the eBay developer portal.
- Basic familiarity with HTTP, JSON, and OAuth 2.0.
Which eBay SDK for Java?
eBay provides SDKs and helper libraries that simplify calling its REST APIs. There are several community and official options; the official eBay REST API Java client (often published on GitHub or Maven Central) helps manage request/response models, endpoints, and authentication helpers. This article uses a typical modern Java client approach (Maven dependency + OAuth2 token retrieval) and raw HTTP examples where appropriate to explain fundamentals you’ll encounter regardless of the exact SDK package name.
Create and configure your eBay developer app
- Sign in to developer.ebay.com and open the Application Keys (or “My Account > Applications”) section.
- Create a new application and note:
- Client ID (App ID)
- Client Secret
- RuName / Redirect URL (for OAuth Authorization Code flows)
- Choose environment keys: sandbox for development/testing, production for live operations. Use sandbox keys for initial development.
Authentication overview
eBay APIs use OAuth 2.0. Two common flows:
- Client Credentials (application-level, for resources that don’t require an eBay user account). Use when the app acts on its own behalf.
- Authorization Code (user-level, for actions on behalf of a seller/buyer). Use when you need access to a user’s eBay account.
For your first API call (e.g., to fetch marketplace metadata), the Client Credentials flow is simplest.
Add dependencies (Maven example)
If an official eBay Java SDK is available on Maven Central, add it. If not, you can use a small HTTP client (OkHttp or Apache HttpClient) and a JSON library (Jackson or Gson). Example Maven POM snippet using OkHttp + Jackson:
<dependencies> <dependency> <groupId>com.squareup.okhttp3</groupId> <artifactId>okhttp</artifactId> <version>4.11.0</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.15.2</version> </dependency> </dependencies> If you prefer using an official eBay SDK package (example artifact coordinates — check current docs for exact names/versions):
<dependency> <groupId>com.ebay</groupId> <artifactId>ebay-sdk-rest</artifactId> <version>1.0.0</version> </dependency> Getting an OAuth token (Client Credentials)
Example using OkHttp to request an app access token from eBay’s OAuth token endpoint. Replace placeholders with your Client ID and Client Secret, and use sandbox vs production endpoints accordingly.
import okhttp3.*; import com.fasterxml.jackson.databind.ObjectMapper; import java.io.IOException; import java.util.Base64; import java.util.Map; public class EbayAuth { private static final String TOKEN_URL = "https://api.ebay.com/identity/v1/oauth2/token"; // production // For sandbox: https://api.sandbox.ebay.com/identity/v1/oauth2/token public static String getAppToken(String clientId, String clientSecret, String scope) throws IOException { OkHttpClient client = new OkHttpClient(); String credentials = clientId + ":" + clientSecret; String basicAuth = "Basic " + Base64.getEncoder().encodeToString(credentials.getBytes()); RequestBody body = new FormBody.Builder() .add("grant_type", "client_credentials") .add("scope", scope) // e.g., https://api.ebay.com/oauth/api_scope .build(); Request request = new Request.Builder() .url(TOKEN_URL) .post(body) .addHeader("Authorization", basicAuth) .addHeader("Content-Type", "application/x-www-form-urlencoded") .build(); try (Response response = client.newCall(request).execute()) { if (!response.isSuccessful()) throw new IOException("Token request failed: " + response); ObjectMapper mapper = new ObjectMapper(); Map<String,Object> map = mapper.readValue(response.body().string(), Map.class); return (String) map.get("access_token"); } } } Scopes: For Client Credentials you must request app-level scopes available for your application (eBay docs list available scopes). For a simple read-only call you might request marketplace metadata scopes, or use the public endpoints that require no scopes if available.
First API call — Get marketplace metadata (example)
After obtaining an access token, call an eBay REST endpoint. Example: retrieve taxonomy/get_default_category_tree_id or browse/search API for sandbox/production. Below is a simple call to the Browse API search endpoint to search for “laptop”.
import okhttp3.*; import com.fasterxml.jackson.databind.ObjectMapper; import java.io.IOException; import java.util.Map; public class EbayApiExample { private static final String BROWSE_SEARCH_URL = "https://api.ebay.com/buy/browse/v1/item_summary/search"; // For sandbox, use https://api.sandbox.ebay.com/buy/browse/v1/item_summary/search public static void main(String[] args) throws IOException { String clientId = System.getenv("EBAY_CLIENT_ID"); String clientSecret = System.getenv("EBAY_CLIENT_SECRET"); String scope = "https://api.ebay.com/oauth/api_scope"; // adjust scope as needed String token = EbayAuth.getAppToken(clientId, clientSecret, scope); OkHttpClient client = new OkHttpClient(); HttpUrl url = HttpUrl.parse(BROWSE_SEARCH_URL).newBuilder() .addQueryParameter("q", "laptop") .addQueryParameter("limit", "3") .build(); Request request = new Request.Builder() .url(url) .get() .addHeader("Authorization", "Bearer " + token) .addHeader("Content-Type", "application/json") .build(); try (Response response = client.newCall(request).execute()) { if (!response.isSuccessful()) { System.err.println("API request failed: " + response.code() + " - " + response.body().string()); return; } ObjectMapper mapper = new ObjectMapper(); Map<String,Object> json = mapper.readValue(response.body().string(), Map.class); System.out.println(mapper.writerWithDefaultPrettyPrinter().writeValueAsString(json)); } } } Notes:
- Replace scopes and endpoints for the exact API you need.
- Production vs sandbox endpoints differ. Use sandbox credentials while developing.
Using an official eBay Java SDK
If you install the official eBay Java SDK, its client will manage token refresh and model mapping. Typical steps:
- Add SDK dependency to build file.
- Configure the SDK client with Client ID/Secret and environment.
- Use provided client classes and methods (for example, BrowseApi.searchItems()) rather than building HTTP requests manually.
Consult the SDK’s README for exact class names and examples.
Handling responses and errors
- eBay APIs return standard HTTP status codes. 200-series for success, 4xx for client errors, 5xx for server errors.
- Error responses include a JSON body with error details—log them and surface meaningful messages.
- Respect rate limits: eBay returns headers indicating usage and limits. Implement exponential backoff on 429 or 503.
Basic testing and sandbox tips
- Use sandbox environment for all development that modifies listings, inventory, or performs transactions.
- Sandbox may require separate test user accounts — create sandbox users in the developer portal.
- Mock API responses in unit tests using tools like WireMock.
Common pitfalls
- Using production endpoints with sandbox keys (and vice versa).
- Missing or incorrect OAuth scopes.
- Not URL-encoding query parameters.
- Exceeding rate limits without backoff.
Next steps
- Implement Authorization Code flow to act on behalf of real sellers.
- Explore specific APIs: Inventory, Fulfillment, Account, Sell/Marketing, Buy APIs.
- Build retry and caching for frequent read endpoints.
- Add logging, monitoring, and secure storage for Client Secrets.
If you want, I can:
- Provide a ready Maven project (pom + source files) you can clone and run against eBay sandbox.
- Convert examples to Gradle.
- Show Authorization Code flow code for obtaining user-level tokens.
Leave a Reply