Wololock's blog

Some time ago I have found another interesting Groovy related question on Stack Overflow. This time someone was asking about static variants of popular propertyMissing and methodMissing methods. The official Groovy documentation does not explain how to do it - it only explains how to add any static method through metaClass. Today we are going to learn how to define these methods in two different ways.

Groovy is a very powerful language on a JVM platform and with this great power comes great responsibility. There are many language features that are not intuitive for many people that start using Groovy. One of these features is dynamic coercion and type promotion which may cause you a headache if you use it carelessly.

A few days ago I have reached 365 consecutive days on Stack Overflow. In the beginning of July 2017 I have decided to run an experiment - visit Stack Overflow every single day and do something useful to other community members (answer a question, review one of the queues, edit and improve existing questions and so on). Now it is the best time to summarize this experiment and share my thoughts with you.

Some time ago I have found a very interesting question on Stack Overflow about forbidden characters in Groovy script filenames. Let’s use it as an excuse to make a closer look at Groovy script files naming limitations - you will find out that there are none actually.

If you use Groovy for scripting or other similar tasks you probably faced a situation where you get an input as a text and you need to process it e.g. split by some delimiter and continue working with extracted values. In this post I will show you how to do it in 3 different ways.

Unit testing Ratpack handlers has many benefits. In the previous post we have learned how to mock Session object to use it with GroovyRequestFixture. Today instead of mocking we will register SessionModule and then we will use a real session object.

Ratpack allows you unit test handlers using GroovyRequestFixture class. The good thing about this approach is that it does not require running the whole application and you can quickly test if the handler does what you expect. However, if you retrieve objects from Raptack’s registry you will run into a problem - registry in this case is empty.

Some time ago I was interviewed to one of the Java-based projects and I was asked to solve this pretty interesting puzzle. The question was "how to count frequency of a digit in a factorial of number, let’s say 1000". I tried to solve it using Java 8 Stream API, but I guess you see how bad decision it was. Problems like that can be easily solved with pure functional languages and today we are going to find out how to solve this puzzle with Haskell.

Recently I have answered a few questions on Stack Overflow related to Groovy scripts and how they work in combination with closures and delegated objects. Some of use cases may not be intuitive and today I’m gonna show you one of them and explain what happens under the hood.

This blog post is inspired by one of my recent Stack Overflow answers to following question: Grails: why is the Config.groovy file executed during compilation?. Here I’m going to show you step by step what makes grails package command executing Config.groovy script and how I’ve managed to find the answer to that question.