Upcoming  Events

The LJC is delighted to continue our new series of events, aimed at giving all Community members an opportunity to present at an LJC meet-up. If you have an interesting topic to share, these events are for you. You don’t have to be an experienced speaker - we want to hear your story and offer you a friendly, informal platform to practise and improve your presentations. For attendees we want this to be a meeting place, where you can talk and network with other technologists in London. If you’d like to speak at a future event, please submit your talk and bio details here: https://sessionize.com/ljc/ Huge thanks to our friends at Couchbase for hosting this event and supporting our Community. Agenda: 6pm Arrivals 6.20 Welcome from Couchbase 6.30 Presentation 1 7.15 Break for refreshments, kindly provided by Couchbase 7.45 Presentation 2 8.30 Networking 9pm Event closes Speaker: Salman Shah, Senior Software Engineer, Smartsheet Talk: Unlocking Java's Multiprocessing Potential: A Journey from Basics to Virtual Threads Join us on a journey as we explore the evolution of multiprocessing in Java, from its humble beginnings to the recent introduction of virtual threads in JDK 21. We'll delve into the basics of multiprocessing, discussing various techniques and frameworks available, and examine the significance of virtual threads in improving Java's multiprocessing capabilities. This talk will provide a comprehensive overview of the topic, highlighting the benefits and takeaways for attendees. Speaker: Liliia Rafikova, Software Developer, Amazon Web Services Talk: Part 2 of the Deep Dive: Advanced Java Concurrency Advanced Locking Mechanisms Explore beyond basic synchronized blocks: understand ReentrantReadWriteLock and StampedLock for fine-grained concurrency. Learn how to optimize read/write operations, reduce contention, and achieve more predictable performance under heavy load. CompletableFuture and Asynchronous Programming Move from basic futures to CompletableFuture and unlock powerful patterns like chaining, combining, and composing tasks. Discover best practices for error handling, debugging asynchronous flows, and integrating with modern reactive streams (Flow API). Performance Considerations and Tuning Identify bottlenecks such as lock contention and thread starvation. Use tools like Java Flight Recorder, Mission Control, and enhanced garbage collectors (G1, ZGC) to profile, monitor, and fine-tune your applications for maximum throughput and minimal latency. Advanced Topics (Optional) Memory Model & Happens-Before Relationship: Understand the Java Memory Model’s guarantees and how they ensure thread-safe operations. Custom Synchronizers: Learn how to build specialized concurrency constructs using AbstractQueuedSynchronizer. Java Concurrency Enhancements in Recent Versions: Stay current with new features like VarHandle, enhancements to CompletableFuture, and upcoming trends (e.g., Project Loom’s virtual threads). Speaker biogs: Liliia Rafikova, Software Developer, Amazon Web Services I'm an experienced backend software engineer. Having over 10+ years of industry experience with the last 5 years I work on building scalable, highly-available and low latency distributed systems. Main stack: Kafka, Java 17, Rust, AWS Services, SQL/NoSQL databases, Docker Salman Shah, Senior Software Engineer, Smartsheet Traveller, Speaker, Engineer simplifying technology. Build, Value, Repeat. This event is organised by RecWorks on behalf of the London Java Community. The London Java Community is sponsored by Hazelcast, Vonage, Neo4j, and Discover

Join us for another LJC Live event to hear from Java Champion Marit van Dijk from JetBrains, and Senior Software Developer Ryan Healy from our hosts, LMAX. Agenda 6pm Arrivals and drinks 6.20pm Welcome from the LJC 6.25pm Welcome from LMAX 6.30pm Ryan Healy: ‘Stop Testing! (my patience)’ 7.15pm Break for refreshments, kindly provided by LMAX 7.45pm Marit van Dijk: ‘Reading Code’ 8.45pm Q&A and networking 9pm Departures Speaker: Ryan Healey, Senior Software Developer, LMAX Group Title: Stop Testing! (my patience) Synopsis: As developers, we should have two attributes: impatience and laziness. Why? Because overall it will (eventually) make us more productive. In a world where hundreds of streams of information are all fighting for our time and attention, this makes it a precious resource; your impatience can help you save mountains of this sought-after capacity. In this talk, I will show you why you should strive to be impatient and lazy and how you can put that to work. Speaker: Marit van Dijk, Java Champion and Developer Advocate at JetBrains Title: Reading Code Synopsis: As developers, we spend a lot of time learning to write code, while spending little to no time learning to read code. Meanwhile, we often spend more time reading code than actually writing it. Shouldn’t we be spending at least the same amount of time and effort improving this skill? Deliberate practice can help us get better at reading code. Learning how to better read and understand code, can in turn teach us what makes code readable. This might even help us to write code that is easier to read. In this talk we will discuss the benefits of deliberately practicing reading code in a code reading club or session without an IDE, as well as common strategies to navigate a new codebase and familiarise ourselves with the code using the IDE. Speaker bios: Ryan Healey is a Senior Software Developer at LMAX: Proudly impatient and lazy (in a good way, I promise). Developer with over 10 years of programming experience, although he has only been paid for half of that. I am passionate about fast feedback, testing, and generally making my own and the developers around me's lives a little bit easier. Marit van Dijk is a software developer with over 20 years of diverse experience across various roles and companies. As a Java Champion and Developer Advocate at JetBrains, she is passionate about building awesome software in collaboration with amazing people, and making developers’ lives better. Marit is committed to continuous learning and actively shares her expertise in programming, software development, testing, and test automation. Marit regularly presents at international conferences, participates in webinars, and appears on podcasts. Additionally, she writes blog posts and tutorials, creates videos, and is a contributor to the book “97 Things Every Java Programmer Should Know” (O’Reilly Media). This event is organised by RecWorks on behalf of the London Java Community. The London Java Community is sponsored by Hazelcast, Vonage, Neo4j and Discover

Join us for the next LJC roundtable evening. We will be discussing technology, not just Java. We are a bunch of friendly folks who would like to meet in an informal environment and discuss and broadly understand technology. Do you work on some open-source projects or want to contribute to one? Do you want to learn the next hot framework or programming? Do you want to share a piece of code you are proud of or you struggle with? We want to make it an open format and see where that will take us.