Creational patterns were first described in the famous Gang of Four’s Design Patterns. The book presents each pattern in a dedicated chapter and follows a strict structure for each one: intent, motivation, applicability, structure, participants, collaborations, consequences, implementation, sample codes, known uses, and related patterns. The intent pattern presents a succinct goal of the pattern, while the applicability tells when you should use it. For example, here’s an excerpt fo| A Java geek
I’ve quite a lengthy experience with GitHub workflows, but not up to the point where I can claim I’m an expert. However, I recently developed a new workflow, and it prompted me to write this post. Feel free to add your own. What are GitHub workflows? A workflow is a configurable automated process that will run one or more jobs. Workflows are defined by a YAML file checked in to your repository and will run when triggered by an event in your repository, or they can be triggered m| A Java geek
When I first started attending conferences, I diligently tried to write down notes and publish them. It forced me to actively listen to the talks I was attending. With the number of conferences rising, I couldn’t keep the rhythm. When I switched my career path to Developer Advocate, I drastically diminished the number of talks I attended in favor of the hallway track. As a result, the last conference 'report' I wrote was JPrime’s in 2022. This week, I was privileged to speak at DevO| A Java geek
Last week, I described several approaches to OpenTelemetry on the JVM, their requirements, and their different results. This week, I want to highlight several gotchas found across stacks in the zero-code instrumentation. The promise of OpenTelemetry Since its inception, OpenTelemetry has unified the 3 pillars of observability. In the distributed tracing space, it replaced proprietary protocols Zipkin and Jaeger. IMHO, it achieved such success for several reasons: First, a huge industry press| A Java geek
You may know I’m a big fan of OpenTelemetry. I recently finished developing a master class for the YOW! conference at the end of the year. During development, I noticed massive differences in configuration and results across programming languages. Even worse, differences exist across frameworks inside the same programming language. In this post, I want to compare the different zero-code OpenTelemetry approaches on the JVM, covering the most widespread: Spring Boot with Micrometer Tracing| A Java geek
Git has become a fundamental part of our developers' daily routine that it’s hard to remember our lives without it. And yet, most of us use a limited set of commands and options. Today, I want to focus on two commands most developers probably use every day and look at the defaults behind them. git push After git commit, git push is probably the second most used command. I don’t think I’ll teach you anything with this excerpt from the documentation: git-push - Update remo| A Java geek
Pattern matching is a major feature in software development. While pattern matching applies in several locations, its current usage is limited to switch case blocks. I want to compare the power of pattern matching across a couple of programming languages I’m familiar with in this post. I assume that every reader is familiar with the switch case syntax inherited from C. In short: The switch clause references a value-returning statementEach case clause sets another statement; if the value| A Java geek
This is the 8th post in the My journey with Home Assistant focus series. This post will be short, but I hope useful. My home is getting more and more connected, and the number of my automations grow each month. Recently, I equipped my roller shutters with connected Somfy engines so they could roll down automatically when it’s too hot in summer. Spoiler: given the current heatwave, it’s a boon!| A Java geek
Concurrent systems face a delicate balance: enabling high throughput under contention while maintaining low latency and predictable behavior. Traditional locking strategies and naive parallelization often introduce performance bottlenecks through cache contention, false sharing, and excessive context switching. These issues are further exacerbated in Cloud and virtualized environments, where performance unpredictability, noisy neighbors, and limited control over physical resources introduce a...| A Java geek
With years, I accumulated devices on my local network, which in general run on Linux. I meticulously added them to my /etc/hosts/ file, so as not to remember their IP. Something puzzled me, though: my Synology NAS was readily available as nas.local on the network, without doing anything. I have close to zero skills in system administration, so here are my findings. The .local domain We can learn more about .local domain from Wikipedia. The domain name .local is a special-use domain name r| A Java geek
I’ve been eying OpenRewrite for some time, but I haven’t had time to play with it yet. In case you never heard about OpenRewrite, OpenRewrite takes care of refactoring your codebase to newer language, framework, and paradigm versions. OpenRewrite is an open-source automated refactoring ecosystem for source code, enabling developers to effectively eliminate technical debt within their repositories. It consists of an auto-refactoring engine that runs prepackaged, open-source refac| A Java geek
The book was sent to me by Michael Simons. He asked for my feedback: I changed my reading schedule, took a few months, and here it is. Facts 10 chapters288 pages$33.59 (eBook) Note that MotherDuck, a company providing an online service that builds upon DuckDB, offers a free PDF copy. Chapters An introduction to DuckDBGetting started with DuckDBExecuting SQL queriesAdvanced aggregation and analysis of dataExploring data without persistenceIntegrating with the Python ecosystemDuckDB in the| A Java geek
I started this blog as a hobby seventeen years ago, in April 2008. At the time, I had no clue about technical writing. I’m pretty sure it was not even a thing back then: the only content aimed at developers was technical documentation. Since then, the landscape has changed a lot, to the point that companies hire for technical writer positions. I was curious to compare what I learned by doing to the structured approach of a book. I ordered the book last year when it was still being written| A Java geek
This is the 7th post in the My journey with Home Assistant focus series. I recently acquired Netatmo smart radiator valves to manage my rooms' temperature remotely. I’m not skilled at manual tasks, but I could easily replace the old thermo-static valves. I then registered the smart ones in the Netatmo app. Finally, I integrated them in my Home Assistant via the dedicated Netatmo integration. Everything was very straightforward. I noticed that each valve not only allows remote control but al| A Java geek
This is the 6th post in the My journey with Home Assistant focus series. I continue to take care of my Home Assistant. This week, I replaced my original setup with Cloudflare Tunnel.| A Java geek
I’m continuing my series on running the test suite for each Pull Request on Kubernetes. In the previous post, I laid the groundwork for our learning journey: I developed a basic JVM-based CRUD app, tested it locally using Testcontainers, and tested it in a GitHub workflow with a GitHub service container. This week, I will raise the ante to run the end-to-end test in the target Kubernetes environment. For this, I’ve identified gaps that I’ll implement in this blog post: Create| A Java geek
This is the 3rd post in the My journey with Home Assistant focus series. I’m the happy owner of a couple of Philips Hue connected lights for a some years. Some of them are colored, some of them regular. In addition, I bought a sensor to go along with the light I installed in my toilets: it turns on automatically when its detects a movement there. In this post, I want to document how I replaced the proprietary automation with Home Assistant’s.| A Java geek
Home Assistant is a massive beast. It can be overwhelming for a newcomer; it was for me. In this post, I want to describe the underlying model of Home Assistant, which is a good entry point for your home automation journey. The biggest issue in describing the Home Assistant is the number of conflicting sources for this model: The helpers package of the GitHub repositoryThe database; disclaimer: I didn’t find the schema generation in the code, and I wasn’t bold enough to check the d| A Java geek
GitHub offers a way to customize one’s profile by allowing one to create a README in a specific repository, named as your profile, e.g., nfrankel/nfrankel. A couple of years ago, I automated the update of my GitHub profile with up-to-date info: my latest blog posts, my upcoming talks, and the last recorded YouTube talk. I took the time to document how to do it on this blog. At the time, I chose Kotlin scripting because I was proficient enough in Kotlin, but I wanted to learn the scripting| A Java geek
