I recently had a reason to parse a large data set, for another project. I decided that an ideal “large data set” would be my Outlook mail saved archives. Sadly, Outlook for Mac doesn’t output PST files, it outputs OLM archives, which are, essentially, giant zip files full of XML. I was coding this all in Java, so I needed a Java library to parse OLM files.
The resulting source code is here. Schema for OLM XML is here.
I recently had reason to get to know OpenAPI at work, so I decided to become familiar with it. I have a HomeSeer home controller at home, which exposes a JSON API, so I decided to write a Java OpenAPI server to expose the JSON API over OpenAPI. The net result is hsOpenAPI. It exposes…
Commons Math is an Apache library which includes a variety of mathematical tools, including 1st and 2nd-order ODE solvers. In order to familiarize myself with the ODE solvers, I wrote a simple program to solve an RC charging circuit. The circuit has these parameters: R (ohms), the resistance of the resistor C (farads), the capacitance…
Back in the day, Paradox was a pretty amazing database. I recently had a reason to read some Paradox files for a friend, who had a client with a Paradox database. They needed their data out of the database to insert into something more modern. Googling for the file format of a Paradox DB didn’t…
We have an Arctic Spa at our house which we enjoy. Recently, an OpenAPI spec has been published for it, so I decided to write a Java wrapper so I could control the spa myself, and monitor temperature with Prometheus and Grafana. The resulting code is here. The wrapper class “com.khubla.kspa.Spa” takes care of all…
AntlrI4DE is an Eclipse plugin for editing Antlr4 grammars. One of the features I used to really like in the original Antlr IDE was the ability to generate railroad diagrams. It turns out that Antlr4IDE has this feature, so I decided to give it a try. My jvmBasic grammar is here, and you can…
I recently found myself in a situation where mission-critical software was suffering from performance problems due to relying on a remote API which was both slow (as slow as 11sec / transaction), and unreliable. In this case, it turned out that there were multiple applications accessing this API, and every individual application was affected….