Teaching old Streams new tricks By Viktor Klang

Have you ever wanted to perform an operation on a java.util.stream.Stream only to find that the existing set of operations didn't provide what you needed—forcing you to break out early from the Stream and perform the logic outside of it? As a matter of fact, java.util.stream was the first JDK API designed with lambdas in mind and was initially released in JDK 1.8, and ever since then it has allowed Java developers to ergonomically manipulate potentially unbounded streams of data. While the Streams API offers a rich set of operations out-of-the-box, it was always envisioned to offer the capability for user-defined intermediate operations, yet at that time the right way to expose that hadn't been discovered. Until now. In this session we'll demonstrate Gatherers, a potential future API to create and reuse intermediate operations for java.util.stream.Stream, enabling you to perform custom transformations as natural steps in your day-to-day stream processing. Together, let us teach our old streams some new tricks! VIKTOR KLANG Viktor is a software architect in the Java Platform Group at Oracle. In his professional career, spanning over more than two decades, he has focused on enabling developers to solve problems with maximal productivity without sacrificing maintainability. Specializing in developer ergonomics in the realm of concurrent, parallel, and distributed programming; he has contributed to the standard libraries of several major programming languages, been involved in more than a dozen Open Source projects, and has spoken at numerous conferences and universities.