Spring Boot DeferredResult: Handling Async Timeouts and Errors

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This tutorial explains how to use Spring Boot's DeferredResult to handle asynchronous requests without holding servlet threads. It covers creating a DeferredResult with a timeout value and registering callbacks for timeout, completion, and error events. The article includes a complete controller example where long-running tasks run on an executor service and set the result when finished. It also demonstrates error handling, including returning error responses with appropriate HTTP status codes.

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