METACODES.PRO, the parent of mainly three fields of activity of mine, covers topics I consider useful for you, programmers, developers and software engineers: REFCODES.ORG, a Java Open Source Software Toolkit I develop, FUNCODES.CLUB, sample applications I build with the Software Toolkit and a collection of related BLOG POSTS I wrote. In the DOWNLOADS section you find the sample applications ready to run and the LATEST NEWS lists the most recent updates.

Explore Posts

Featured Posts

CRACKZIP manpage

Recovery tool for cracking password protected ZIP (*.zip) files …

6 min read

FLATML manpage

A shell filter flattening markup properties of XML, JSON, YAML, INI or PROPERTIES format to key/value lines …

4 min read

Short-Term effects and Long-Term impacts of AI and Machine Learning

Reasoning upon the current rise of AI and Machine Learning, I scribbled down some thoughts regarding the Short-Term effects and Long-Term impacts of AI and had GPT-4 render my input into a blog post (statements 2. or 3. may apply to this article) …

8 min read

Yet another AI cheat sheet

As AI continues to evolve, I sat down to prepare a structured overview of this topic for me to the have some cheat sheet for looking up related terms and definitions quickly …

20 min read

Yet another VI(M) cheat sheet

The ACNS Bulletin ED–0 «vi Editor “Cheat Sheet”» from the University at Albany, updated with some copy’n’ paste hints and visual modes outlined (as I tend to forget how to invoke the most essential vi functionality) …

4 min read

Yet another Big-O cheat sheet

Unlock the algorithmic secrets with this Big-O Notation cheat sheet, decoding runtime behaviors in a sentence …

4 min read

refcodes-cli: Parse your args[]

Just about everything you’ll need to comfortably parse your Java command line arguments …

13 min read

Java deliverables as executable bundle and the launcher trick

In the past I coded some command line tools in Java which are quite useful for me and which I ought to be useful for others. Providing just fat JAR files implies launching of those Java applications to be more or less cumbersome …

13 min read

Yet another BASH cheat sheet

The tiny BASH Cheet Sheet provides you (me) with a more or less alphabetically sorted tool-box of the expressions I most commonly use and tend to forget …

13 min read

Buchtipp: Spring for GraphQL

Reckoning the book »Spring for GraphQL« from Michael Schäfer very helpful, the Javamagazin 8/22 published an according book review I wrote …

~1 min read

PASSGEN manpage

A tool for generating password lists written into a file or printed to <STDOUT> by providing rule expressions …

3 min read

Better programs - Citations one should have heard of (1/2)

The last years I stumbled over notable citations and excerpts or even parodies and other bits and pieces which I regard should accompany good software engineers to produce better code …

11 min read

PLAYLOAD manpage

Peer-to-Peer command line transport system for exchanging messages between peers over serial TTY (COM) ports …

4 min read

ASCART manpage

A command line tool for creating ASCII art (“[ASC]II[ART]”) from plain text or image files …

3 min read

BIN2TXT manpage

Encoding and decoding tool for BASE64 and related encodings/decodings from/to ASCII to/from binary …

2 min read

Chaos-based encryption - revisited!

How to use the CHAOS command line tool to evaluate Chaos-based encryption alongside a comparison to the AES algorithm.

17 min read

TELETYPE manpage

Teleprinter command line tool for sending data to and receiving data from TTY (serial) ports simultaneously.

3 min read

HTTPECHO manpage

Small HTTP-Echo server echoing incoming HTTP-Requests back to the client and to the console …

2 min read

AUTOCHAT manpage

ELIZA chatbot (by Joseph Weizenbaum) talking to you via RESTful services and an MS-Teams endpoint or on the console …

2 min read

WATCHDOG manpage

Cellular automaton simulating a watchdog in a house using JavaFX …

2 min read

PICDAT manpage

Tool for converting (raw) data to a pixmap image and extracting raw (pixmap) data from an image …

2 min read

CHAOS manpage

Encryption and decryption tool of file or stream data using Chaos-based encryption …

7 min read

TTY2MQTT manpage

Tool bridging between a serial port and an MQTT message broker for publishing or subscribing messages …

5 min read

PIXGRID manpage

Tool for displaying a light bulb matrix rendering configurable scrolling and fading pixmaps (PNG, GIF or JPG) …

3 min read

WAVES manpage

Tool to generate or pipe and filter (sound) waves for audio playback and export.

2 min read

DADUM manpage

Tool for dumping mass data by pattern to files or streams …

2 min read

Manpages online!

The manpages for the FUNCODES.CLUB commands are online now!

~1 min read

Autumn leaves, Terminate and Stay Resident!

In the year 1991, I coded a TSR program simulating the effect of the Cascade Virus (also known as the Herbstlaub Virus) as of my best imagination … now it turns out that it’s the Cascade Virus’ effect on speed!

16 min read

Listings im Kilo-Pack: Die Dateien von heute

I was very proud when in October 1992 the computer magazine »DOS International« published a 1024 bytes short Turbo Pascal program I wrote …

3 min read

Java Profiler sponsored by JProfiler

As of today, REFCODES.ORG’s open source software is profiled with JProfiler thanks to ej-technologies’s OSS support initiative.

~1 min read

The mystery of three letter acronyms

Playing around with three letter acronyms (TLA) seems to have some history in computing. You’ll find them in SciFi movies or in the naming of some products.

2 min read

Ed Post über JavaScript (3/3)

Ed Post im Interview: “Ist JS (k)eine General Purpose Sprache?” und viele Fragen zu JavaScript werden beantwortet.

6 min read

Ed Post über JavaScript (2/3)

Ed Post im Interview: “Ist JS (k)eine General Purpose Sprache?” und viele Fragen zu JavaScript werden beantwortet.

28 min read

Ed Post über JavaScript (1/3)

Ed Post im Interview: “Ist JS (k)eine General Purpose Sprache?” und viele Fragen zu JavaScript werden beantwortet …

14 min read

Restful JShell … RestREPL your Java 9’s JShell!

Java 9’s JShell can not only be used as a command line tool, furthermore you can use it in your own Java application. Learn on how to harness the JShell by building a restful service around it.

7 min read

All-in-one Java configuration properties at hand

Learn on how to use the all-in-one runtime configuration properties giving you all the power of the various configuration features with a single line of code …

6 min read

Automatically obfuscate your Java application’s configuration

Secure your application’s sensitive properties (passwords, secrets or access keys) on your hosts, on a host-, user- and/or application-individual context, and learn on how to use the all-in-one runtime configuration properties …

7 min read

Bare-Metal REST with just a few lines of code

On building slim RESTful services and REST clients without a Heavy-Weight framework doing magic in the background and with a little help from Java 8’s lambda expressions.

8 min read

The canonical model, an ace upon your sleeve

Learn how the canonical model pattern helps you harness a bag full of functioanlity whilst keeping your effort low (and making the bits and pieces fit together magically) …

3 min read

Dead simple Java application configuration

Retrieve (and store!) your YAML, TOML, JSON, XML or whatever (profiled) properties from various locations, resources or folders, just as you need it!

5 min read

JVM-Con 2017 in Cologne

This year I have been at the JVM-Con 2017 in Cologne as a speaker, the topic being »About sense and nonsense on extensive framework use« …

1 min read

No more Mr. Nice Guy, no more code reviews!!!

No more code reviews, Mr. Nice Guy! Did you ever spend more than one second on thinking about WHO has to use your code’s INTERFACES ?!? Go away code review, I want good interfaces …

5 min read

Yet another REST cheat sheet

I believe that good interfaces are even more important than good code. Refactoring a bad interface bears far-reaching implications effecting the interface implementation(s) as well as all the interface consumers …

5 min read

The utility-builder pattern

Combining a utility class’s functionality with the builder pattern, add some spicy properties to it, and here comes the utility-builder pattern. Let’s try a definition …

8 min read

Off topic summertime workshops

Summer break is over and I wasn’t lazy … trying to get an electrified flight plane into the air and refurbishing an old Merkur VISION arcade cabinet …

2 min read

refcodes-jobbus: Asynchronous job execution

Push your jobs onto the job-bus, let the job-bus execute your jobs asynchronously and grab the results later on - don’t bother with where (local or remote) your jobs are being executed …

3 min read

Verschlüsselung im Chaos (Chaos-based encryption)

This text I received in the late 1980s in Harare (Zimbabwe ) from the mathematician Sönke Rehder; back then as a pupil I coded the herein described algorithm in BASIC on an Atari 600XL …

8 min read

Publish … subscribe … observe … event-bus?

Lately some colleagues and me were reasoning on how to do client-side communication between web-page components … with Java I recommend taking a look at the refcodes-eventbus …

1 min read

refcodes-command: Do the undo

Ever wondered how to easily implement and extend your application’s undo functionality?

8 min read

Logging like the nerds log

An introduction to the refcodes-logger framework; let’s start with giving your logs some color and tidy them up! Then let’s take over spring-boot’s log output …

2 min read


My blog to accompany my org.refcodes Java based Maven artifacts

~1 min read
Back to Top ↑