# Java SDK

Welcome to the Market Data Java SDK documentation. This SDK lets you integrate Market Data services into any JVM application. It ships typed, records-based responses, sync **and** async (`CompletableFuture`) variants for every endpoint, automatic retries and rate-limit tracking, and a sealed exception hierarchy you can branch on exhaustively.

The SDK is written in Java (JDK 17+) with no Kotlin runtime dependency, but it is designed to be **idiomatic from Kotlin too**: nullability is annotated (no platform types), the client is `AutoCloseable` (so `use {}` works), and async methods return `CompletableFuture`, which Kotlin interops with directly.

## Quick Start

### Java

```java
import com.marketdata.sdk.MarketDataClient;
import com.marketdata.sdk.stocks.StockQuoteRequest;

// The no-arg constructor reads MARKETDATA_TOKEN from the environment (or a .env file)
// and validates it on startup. The client is AutoCloseable.
try (MarketDataClient client = new MarketDataClient()) {

  // A single quote — quote(...) returns a list; a single symbol is row 0.
  var quote = client.stocks().quote(StockQuoteRequest.of("AAPL")).values().get(0);
  System.out.println(quote.symbol() + " last=" + quote.last());
}
```

### Kotlin

```kotlin
import com.marketdata.sdk.MarketDataClient
import com.marketdata.sdk.stocks.StockQuoteRequest

// `use {}` closes the client when the block ends — the Kotlin equivalent of try-with-resources.
MarketDataClient().use { client ->
    val quote = client.stocks().quote(StockQuoteRequest.of("AAPL")).values()[0]
    println("${quote.symbol()} last=${quote.last()}")
}
```

## Open Source

The SDK is open source and available on GitHub. Feel free to contribute to the project, report bugs, or request new features.

- [Java SDK on GitHub](https://github.com/MarketDataApp/sdk-java/)

## Documentation

The best source for documentation on the SDK is right here. This documentation is the most up-to-date and accurate source of information on the SDK.

## Using the SDK

This SDK is designed to help you get up and running with Market Data's APIs as quickly as possible, providing all the tools you need to access real-time stock and options prices, historical data, and much more.

### Getting Started

1. [Install the SDK](https://www.marketdata.app/docs/sdk/java/installation) into a Gradle or Maven project.
2. Set up your [authentication token](https://www.marketdata.app/docs/sdk/java/authentication) to access the API.
3. Learn about the [client](https://www.marketdata.app/docs/sdk/java/client) and how to make your first API requests.
4. Configure [Settings](https://www.marketdata.app/docs/sdk/java/settings) to customize output format, date format, and other universal parameters.
5. Explore the available endpoints for [stocks](https://www.marketdata.app/docs/sdk/java/stocks), [options](https://www.marketdata.app/docs/sdk/java/options), [funds](https://www.marketdata.app/docs/sdk/java/funds), [markets](https://www.marketdata.app/docs/sdk/java/markets), and [utilities](https://www.marketdata.app/docs/sdk/java/utilities).

### Support

- If you have any questions or need further assistance, please don't hesitate to open a ticket at our [helpdesk](https://www.marketdata.app/dashboard/).
- If you find a bug you may also [open an issue in our GitHub repository](https://github.com/MarketDataApp/sdk-java/issues). Please only open issues if you find a bug. Use our helpdesk for general questions or implementation assistance.