Java/Kotlin general availability

The Java and Kotlin SDK generators are now generally available, with improved support for complex OpenAPI specs and several new features.

• Convenient builders for complex objects: The SDKs now include helper methods to make building complex objects easier, such as .addCard(Card) alongside .cards(List<Card>) or .addUserMessage(String) for a discriminated union like {role: 'user', message: string}.
• Automatic cleanup for unreachable objects: The HttpClient and other resources are now closed automatically when no longer in use, even if the user forgets to call .close() (available in Java 9+).
• File uploads: Multipart form data is fully supported, even with nested file fields. Builders like FileCreateParams.builder().file(...) accept byte[], InputStream, or Path, and stream data directly to the API, without buffering in-memory whenever possible.
• Binary responses: Methods like client.files().retrieve(...) return an HttpResponse with a .body() stream. This is ideal for handling binary data without loading it all into memory.
• Raw response access: Easily access headers and more for any method call; for example, client.cards().withRawResponse().create(...) returns an HttpResponseFor<Card> with .headers(), .parse(), etc.
• SSE and JSONL streaming: Endpoints with streaming responses are now supported (e.g., client.chat().completions().createStreaming()).
• Jackson compatibility: The SDKs work with Jackson versions as old as 2.13.4, minimizing the chance of version conflicts in downstream applications.

We have a slew of additional improvements to our Java SDKs planned; please reach out to [email protected] with anything you’d be most excited to see.