The maxParallelForks property runs test classes in parallel, but not individual tests in a class. Read More
Solving the Daily Jumble
Recently I decided to subscribe to my local newspaper (the Hartford Courant, pronounced current) again. That’s been valuable by itself, and brought some benefits I forgot about (like a comics page), but one of the unexpected side effects has been the Daily Jumble. The idea is to unscramble the clues to form words. All of… Read More
Are you positive you tested positive?
If we ever hope to break out of our current pandemic isolation, we need tests to determine who has COVID-19 and who doesn’t. No test is perfect, however, which means any test is going to result in false positives, especially if you are trying to measure a very weak signal. The purpose of this post… Read More
Why Use Mocks?
Testing A Simple Publisher/Subscriber System With Mockito One of the challenges I find when teaching Java testing with Mockito is that the docs, while complete, don’t motivate why you want to use mocks in the first place. This post includes a simple example to show why mocking frameworks are important and where they are useful.… Read More
Antarctica Time Zones in Kotlin on GraalVM
They say you can tell someone is a developer by whispering the word “timezone” in their ear and watching a shudder go down their spine. Here, from Wikipedia, is a picture of the time zones in Antarctica. Amazing, right? But the funny part isn’t immediately obvious. See how the South Pole is inside that hashed… Read More
A Few Astronomical Examples in Kotlin
The website Open Notify provides a few URLs that return JSON data from NASA. There are currently three links supported: Number of people in space Current location of the International Space Station Overhead pass predictions for the ISS Just for fun, this blog post uses Kotlin to access each one, transform the results in Kotlin… Read More
Fibonacci in Kotlin
I didn’t realize it until I noticed the trending topic on Twitter, but Saturday, November 23 was Fibonacci Day. That gave me an opportunity to drag out one of my favorite old jokes: For those unaware or who don’t remember, the Fibonacci series starts with 0 and 1, and then each subsequent number is the… Read More
Annotated TOC for Kotlin Cookbook
Last week I received an email asking about a table Of contents for my new Kotlin Cookbook, saying they couldn’t find one either on the O’Reilly Media site or on Amazon. It’s a lot easier to make a decision about buying a recipe book if you have a list of recipes. When I checked last… Read More
Kotlin Palindrome Checker
This post, based on code from my new Kotlin Cookbook, shows how to write a palindrome checker in Kotlin. Along the way it discusses raw strings and regular expressions, writing functions as single statements, and creating an extension function on String. First, a quick definition. A palindrome is a string whose characters are the same… Read More
A Deep Dive into the KotlinVersion Class
Getting the current Kotlin version is easy, but the actual KotlinVersion class is much more interesting. This post shows how to get the Kotlin version programmatically, but then looks at the details of the KotlinVersion class, including how it demonstrates a great way to write an equals method and more. Note that this demo is… Read More