St. Louis Java User's Group

We know that test automation is often discussed as a “best practice” in modern software development, but why should we love automated testing as a developer? In this presentation, we will learn how reliance on manual testing and processes for validation lies at the heart of some of the most challenging problems in software development. We will then cover practices and principles for developing reliable, portable, and maintainable automated tests. This will help developers not view automated testing as a chore but as a central aspect of our work that helps us deliver better customer service!

Note: This is a hybrid online/in-person meeting. Food and social begins at 6pm for those in the training room. Meeting begins at 6:30pm for those online and in the training room.

MySQL Document Store offers developers the best features of NoSQL and relational, SQL-based databases. In this session, we will discuss how we can use Java to access a MySQL Document Store, create/remove collections, create/update/remove documents, retrieve, filter, & sort document lists, and leverage raw SQL to retrieve aggregate data for reporting purposes.

Note: This is a hybrid online/in-person meeting. Food and social begins at 6pm for those in the training room. Meeting begins at 6:30pm for those online and in the training room.

Cloud computing and microservices changed how we approach software development, but the inherent challenges of distributed systems force developers to deal with failures, timeouts, and retries, leading to complex code that's difficult to debug and cumbersome to maintain. Even worse, software and hardware defects can cause applications to crash, resulting in incorrect behavior due to loss of application state.

Failures are inevitable, but as you’ll see, they need not be disruptive. During this talk, you’ll learn about Durable Execution, which is based on nearly two decades of work on large-scale distributed systems at Amazon, Microsoft, and Uber. You’ll also learn the basics of Temporal, an open source Durable Execution platform that resulted from this work. Through code walkthroughs and live demonstrations, you’ll see how a Java application is able to overcome failure scenarios, including a service outage and an application crash.

Note: This is a hybrid online/in-person meeting. Food and social begins at 6pm for those in the training room. Meeting begins at 6:30pm for those online and in the training room.

Getting familiar with complicated technical topics like concurrency or recursion, we often look to abstractions. We boil things down to diagrams with boxes and arrows, tucking the details away for later.

While often a great starting point, there’s a lot of value in pushing the other direction too. On the JVM, reality isn’t your Java, Kotlin, or Clojure code -- it’s the bytecode running below the surface. Surprisingly, many elusive topics may actually be clearer when we can understand what’s happening at that layer below.

In this talk, we’ll get up to speed on just enough bytecode reading to start exploring real topics like lost writes from concurrency, tail recursion, and co-routines. We’ll get familiar with the basic tools and opcodes, what to do when the bytecode’s hard to understand, and come away more confident in our ability to understand our systems from top to bottom.