Deep Dive into Gatherers - JEP Cafe 24

Explore the comprehensive capabilities of Gatherers, a powerful new feature added to JDK 24 and available in JDK 25 for business applications. Master the fundamentals of mapping and filtering operations while learning to create and manage internal mutable states for stream limitation and sorting. Discover proper techniques for interrupting streams when necessary and avoid common pitfalls like resource leaking and race conditions when using the API. Learn to leverage performance optimizations by declaring integrators as greedy when appropriate. Understand how to implement parallel Gatherers and use non-parallel Gatherers effectively within parallel streams. Gain hands-on experience writing various types of Gatherers including mapping, filtering, flat-mapping, skipping, limiting, distinct, and sorting implementations. Learn to work with the Downstream object, handle rejecting states, ensure thread safety, and properly close streams. Explore advanced topics such as using Finishers with TreeSet implementations, creating parallel Gatherers with Combiners, chaining Gatherers with the andThen() method, and utilizing the mapConcurrent() factory method. By the end of this comprehensive tutorial, develop the expertise to write efficient and correct Gatherers while understanding when to use them and when alternative approaches are more appropriate.