java

Are you looking for a collection of code snippets showcasing interesting and useful features of the Micronaut Framework? You’ve found the right place!

In this blog post, I show you how to build stackoverflow-cli - a command-line application that allows you to search Stack Overflow questions directly from the terminal window. I use Java 11+, Micronaut, Picocli, and GraalVM’s native-image.

Dynamic type inference in Groovy might be tricky. Add generic type erasure to it, and you can find yourself in trouble. In this blog post, I would like to show you such use case and explain what happens under the hood. Enjoy reading!

In one of the latest blog posts, I have shown you how you can build a Docker image with Java and Maven installed with the SDKMAN! command-line tool. Today I would like to continue the topic and show you, how you can compile your project using two different Java versions in parallel.

I started reading "Cracking the Coding Interview, 6th Edition" book recently and it inspired me to experiment a bit. It’s been a while since I implemented the quicksort algorithm the last time, and I did that in Haskell. I remember some old and imperative implementations in Java, but I never tried to implement it in Groovy. Let’s give it a try!

In the last article, I have shown you how you can build a docker image for Jenkins Pipeline using SDKMAN! command-line tool. Today I will show you how you can build multiple different docker images using parallelized Jenkins Pipeline.

A few days ago, I was struggling with some Docker images I use in my Jenkins CI environment. I run some Jenkins Pipelines, and I like to define build environment as code using custom Docker images. Everything was fine until I had to consider running different Java or Maven versions. I decided to use one of my favorite command-line tools - SDKMAN!, to build a highly configurable build environment.

In this short blog post, I would like to show you how to set a heap size of the application executed from the native image generated with GraalVM. We will also take a quick look at the effects caused the maximum heap size change.

I love SDKMAN!. It made using multiple different Java distributions in a single operating system much more comfortable. You can install Java across different versions (from 6 to 13.EA) and different vendors (OpenJDK, Oracle, Zulu, Corretto or GraalVM CE to name a few). Switching between those versions is as simple as executing a single sdk use java {version} command and you are ready to use whatever Java you want. However, not all Java versions are available by default, but luckily, SDKMAN! has a simple solution to this problem.

In the second part of the "Groovy Regular Expression" blog post, I want to show you some benchmarks. And let me make one thing clear - the following results you are going to see are not scientific proof. I present those results only to give you a hint about the overall performance of some cool features you have seen before.

The journey inside the exciting world of GraalVM continues. Today I would like to share with you results of running Ratpack on GraalVM experiment. You are going to learn how to build a native binary of a simple "Hello, World!" Ratpack application. In the end we are going to run some benchmarks to see if running GraalVM executable produces better results than running JAR on a regular Oracle JDK.

We have learned how to create GraalVM native image from standalone Groovy script in the previous blog post. Today we continue the experiments, and this time we are going to create a Docker image to see what are the benefits and drawbacks of this solution.