Structured Concurrency in Java: The What & Why • Balkrishna Rawool • GOTO 2023

This presentation was recorded at GOTO Amsterdam 2023. #GOTOcon #GOTOams https://gotoams.nl Balkrishna Rawool - IT Chapter Lead at ING RESOURCES https://twitter.com/BalaRawool https://github.com/balkrishnarawool https://www.linkedin.com/in/balkrishnarawool ABSTRACT This talk introduces Virtual Threads and Structured Concurrency and explains their benefits and shortcomings. It compares Structured Concurrency API with CompletableFuture API by live coding multiple examples with both of these APIs. Virtual threads are lightweight user threads, enabling Java applications to produce thousands (or even millions) of threads. Also, they are super-efficient as they don't block their 'carrier' threads. These two characteristics of virtual threads let application developers focus on business requirements rather than managing platform threads (for example, with thread-pools etc.) which enables Structured Concurrency. With structured concurrency, we can let each business-task be executed by a separate virtual thread and structure these virtual threads in any logical way that we want. It provides us with control structures for managing our virtual threads and simplifies applications that use concurrency. A big part of the talk is live coding where multiple examples are first implemented with CompletableFuture and then with Structured Concurrency API. For each example, these two implementations are then compared. These examples highlight that CompletableFuture’s reactive-like API relies on callbacks whereas Structured Concurrency puts forward an imperative-like API which is easier to read and reason. All in all, this talk introduces virtual threads and structured concurrency to the audience and explains why one should seriously consider using it. [...] TIMECODES 00:00 Intro 00:27 Project Loom 01:55 How to create virtual threads? 03:53 Demo 06:55 Virtual Threads continued 08:28 Demo 09:07 Virtual Threads continued 10:53 Structured Concurrency 14:42 CompletableFuture API vs Structured Concurrency API 15:09 Demo 38:55 Shutdown policies 40:43 Outro Download slides and read the full abstract here: https://gotoams.nl/2023/sessions/2770 RECOMMENDED BOOKS Jeff Scott Brown & Graeme Rocher • The Definitive Guide to Grails 2 • https://amzn.to/3DdcugY Todd Raymond Sharp • Introducing Micronaut • https://amzn.to/3pFvt0v Sanjay Patni • Pro RESTful APIs with Micronaut • https://amzn.to/43qekpp Nirmal Singh & Zack Dawood • Building Microservices with Micronaut • https://amzn.to/43mKfH5 https://twitter.com/GOTOcon https://www.linkedin.com/company/goto- https://www.facebook.com/GOTOConferences #Java #Java21 #Concurrency #StructuredConcurrency #VirtualThreads #API #ProjectLoom #PlatformThreads #CompletableFuture #ING #Pinning #BalkrishnaRawool Looking for a unique learning experience? Attend the next GOTO conference near you! Get your ticket at https://gotopia.tech Sign up for updates and specials at https://gotopia.tech/newsletter SUBSCRIBE TO OUR CHANNEL - new videos posted almost daily. https://www.youtube.com/user/GotoConferences/?sub_confirmation=1