After writing some Java code for validating certificate-based digital signatures I go into daydream mood. Only for geeks, with apologies. Continue »

I’m nearing completion of my first serious project based on sqlite. It’s been there for ages, but it’s always been a niche database. Until now I haven’t found an occasion to use it. Now, having had a close encounter, I’m impressed. Continue »

Java developers have waited a long time for JShell. It’s here now. Is it really what we waited for? Sorry, but some doubts linger on my mind. Continue »

Your project is already late when you discover in the small print of the contract that the system in development “SHALL manage Roman digits in chapter numbers”. You frantically search the ‘Net and, yes there are solutions. Some of them seem complicated on first sight. Do you wish for less convoluted code? You’ve got it.
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I’m a Java ecosystem person but most of the code I write is Groovy. There are occasional patches of Java, but my mind is tuned in to Groovy. In a recent project I had to stay all-Java for a while. A little data structure turned up that I decided would benefit from being converted to JSON and then stored in a database.

If you didn’t know, converting to/from JSON are one-liners i Groovy. You hardly even think about it. I had to search the ‘Net to find out how it’s done in Java these days. Gson seemed a solid candidate, but I was in for a surprise. In the end I chose a completely different approach which is also an editor’s choice.
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My new workhorse laptop (running Ubuntu Linux) had disturbing symptoms. Never have I had to use the power button so often to shut down a Linux box. Mystery. Linux traditionally has been a bedrock of stability. It took me a while to realize that a handful of problems point in the same direction: systemd.
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Grails is a powerful framework for building cool stuff in Groovy. This post is about structuring the layout of web applications to avoid copy-paste. Grails contains several powerful mechanisms for this purpose. The official documentation on some of them is strangely vague. This note is a snapshot of my own understanding, a work in progress.
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Over the years there has been no shortage of Groovy modes for Emacs. They all had an irritating tendency to stumble even on common language constructs. I was very happy to find a new version that seems to get things right.
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A previous post introduced the filestat package for accessing low-level file attributes from Java on a Unix/Linux platform. The recently released Java 7 includes functionality for doing that job and a lot more.
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Groovy has a number of simple and useful methods that are almost impossible to find by a web search. Try as you wish, googling for any, find, or count just gets you a giant haystack hiding the proverbial buried needle. And… hey, what was the name of that method that lets you insert a value into an iteration, kind of?

This post is about those Groovy methods that are all over the place, and yet hard to find. I wrote it as a reminder to myself.
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