Author Archives: Markus Karg

About Markus Karg

Java Guru with +30 years of experience in professional software development. I travelled the whole world of IT, starting from Sinclair's great ZX Spectrum 48K, Commodore's 4040, over S/370, PCs since legendary XT, CP/M, VM/ESA, DOS, Windows (remember 3.1?), OS/2 WARP, Linux to Android and iOS... and still coding is my passion, and Java is my favourite drug!

Coding Microservice From Scratch (Part 8) | JAX-RS Done Right! | Head Crashing Informatics 73

Posted on 18. March 2023 by Markus Karg

Write a pure-Java microservice from scratch, without an application server nor any third party frameworks, tools, or IDE plugins — Just using JDK, Maven and JAX-RS aka Jakarta REST 3.1. This video series shows you the essential steps! You asked … Continue reading →

Posted in Jakarta EE, Java, Lectures, Microsoft, Programming | Tagged , , , , , | Leave a comment

Speed it up by throwing it away | Maven Contribution | Java Coding | Head Crashing Informatics 72

Posted on 4. March 2023 by Markus Karg

For a third time, I speeded up Plexus-Utils, which is the workhorse underlying #Maven. This time, simply by throwing code away! If you like this video, please give it a thumbs up, share it, subscribe to my channel, or become … Continue reading →

Posted in Java, Open Source, Programming, Projects | Tagged , , , , , , , , , | Comments Off on Speed it up by throwing it away | Maven Contribution | Java Coding | Head Crashing Informatics 72

Speed up your I/O with Java 11 | Maven Contribution | Java Coding | Head Crashing Informatics 71

Posted on 18. February 2023 by Markus Karg

I modified Plexus-Utils, which is the workhorse underlying #Maven, once again. This time, to copy data faster using #Java 11’s NIO APIs. If you like this video, please give it a thumbs up, share it, subscribe to my channel, or … Continue reading →

Posted in Java, Open Source, Programming, Projects | Tagged , , , , , , , , , | Comments Off on Speed up your I/O with Java 11 | Maven Contribution | Java Coding | Head Crashing Informatics 71

Speed up your I/O with Java 7 | Maven Contribution | Java Coding | Head Crashing Informatics 70

Posted on 4. February 2023 by Markus Karg

I modified Plexus-Utils, which is the workhorse underlying #Maven, to copy data faster using #Java 7’s NIO APIs. If you like this video, please give it a thumbs up, share it, subscribe to my channel, or become my patreon https://www.patreon.com/mkarg. … Continue reading →

Posted in Java, Open Source, Programming, Projects | Tagged , , , , , , , , , | Comments Off on Speed up your I/O with Java 7 | Maven Contribution | Java Coding | Head Crashing Informatics 70

Double Performance! | OpenJDK Contrib | Java Coding | Head Crashing Informatics 69

Posted on 21. January 2023 by Markus Karg

Yes, I really did it! My latest contribution to #OpenJDK 21 will make your #Java program drive I/O bytes up to twice as fast through your streams. If you like this video, please give it a thumbs up, share it, … Continue reading →

Posted in Java, Open Source, Programming, Projects | Tagged , , , , , , , , , , | Comments Off on Double Performance! | OpenJDK Contrib | Java Coding | Head Crashing Informatics 69

#letsplay? | The Two Minutes Tuesday 036 | Announcement

Posted on 10. January 2023 by Markus Karg

Would you like to see me streaming a #java live coding #letsplay episode? Tell me your opinion in the video comments on Youtube! If you like this video, please give it a thumbs up, share it, subscribe to my channel, … Continue reading →

Posted in Java, Open Source, Programming, Projects, The Two Minutes Tuesday | Tagged , , , , , | Comments Off on #letsplay? | The Two Minutes Tuesday 036 | Announcement

SequenceInputStream boosted: Latest OpenJDK Contrib | Java Coding | Head Crashing Informatics 68

Posted on 31. December 2022 by Markus Karg

If you are using SequenceInputStream, you will notice that it pulls all data into the JVM’s memory, just to drain it to another I/O sink. This is inefficient and slow. With my latest contribution contained in #OpenJDK 20, this will … Continue reading →

Posted in Java, Open Source, Programming, Projects | Tagged , , , , , , , , , , | Comments Off on SequenceInputStream boosted: Latest OpenJDK Contrib | Java Coding | Head Crashing Informatics 68

Small Change with BIG EFFECT | OpenJDK Contrib | Java Coding | Head Crashing Informatics 67

Posted on 17. December 2022 by Markus Karg

Contributions to #OpenJDK don’t have to be huge always. Sometimes it is the small things that have BIG EFFECT. For example if a class was intended to be non-synchronized (hence: fast), implicitly is synchronized by mistake (hence: slow), is finally … Continue reading →

Posted in Java, Open Source, Programming, Projects | Tagged , , , , , , , , , , | Comments Off on Small Change with BIG EFFECT | OpenJDK Contrib | Java Coding | Head Crashing Informatics 67

I boosted the PushbackInputStream | OpenJDK Contrib | Java Coding | Head Crashing Informatics 66

Posted on 3. December 2022 by Markus Karg

As #PushbackInputStream is quite similar to #BufferedInputStream, it was rather easy for me to apply the performance optimizations I already developed for BufferedInputStream to the PushbackInputStream. The contribution was accepted in November 2022, so it is now part of #OpenJDK … Continue reading →

Posted in Java, Open Source, Programming, Projects | Tagged , , , , , , , , , , | Comments Off on I boosted the PushbackInputStream | OpenJDK Contrib | Java Coding | Head Crashing Informatics 66

BufferedInputStream boosted AGAIN by OpenJDK Contrib | Java Coding | Head Crashing Informatics 65

Posted on 19. November 2022 by Markus Karg

Recently I boosted #BufferedInputStream by contributing to #OpenJDK. There was one case open, in which performance did not excel. Now in my new contribution to OpenJDK, which is contained in #Java 20, I fixed this – so in two thirds … Continue reading →

Posted in Java, Open Source, Programming, Projects | Tagged , , , , , , , , , , | Comments Off on BufferedInputStream boosted AGAIN by OpenJDK Contrib | Java Coding | Head Crashing Informatics 65