Part 1: Java to native using GraalVM
One of the most amazing projects I’ve learned about this year is GraalVM.
I’ve learned about this project during Devoxx Poland (a Polish developer conference) at a talk by Oleg Šelajev. If you’re curious about everything GraalVM has to offer, not just the native Java compilation, please watch his video.
GraalVM is a universal/polyglot virtual machine. This means GraalVM can run programs written in:
- Javascript
- Ruby
- Python 3
- R
- JVM-based languages (such as Java, Scala, Kotlin)
- LLVM-based languages (such as C, C++).
In short: Graal is very powerful.
There is also the possibility to mix-and-match languages...
Part 2: OpenJ9 versus HotSpot
Intro
Yesterday I compared different JDK versions and OpenJ9 versus HotSpot on memory and speed. The memory part of the test was realistic if you ask me, an actual working Spring Boot application that served REST objects.
The speed/CPU test however was… lacking. Sorting some random arrays, just one specific test.
Today I decided to test OpenJ9 and HotSpot a bit more using an actual benchmark: SPECjvm2008.
SPECjvm2008
SPEC (Standard Performance Evaluation Corporation) has a couple of well defined benchmarks and tests, including an old JVM benchmark called SPECjvm2008. This is an elaborate benchmark testing...
Part 1: OpenJ9 versus HotSpot
TLDR;
OpenJ9 and IBM J9 are a different JVM implementation from the default Oracle HotSpot JVM. With the modern adoptopenjdk pre-made Docker images it is easy to swap and test different combinations and pick the right JVM for you.
The rumours seem to be true, OpenJ9 seems to blow HotSpot away on memory usage. HotSpot seems to have the edge CPU-wise.
OpenJ9
In the Java world most people are familiar with OpenJDK. This is a complete JDK implementation including the HotSpot JVM engine. Not a lot of developers know or try alternatives to HotSpot. Asking...
Java and Docker, the limitations
TLDR;
Java and Docker aren’t friends out of the box. Docker can set memory and CPU limitations that Java can’t automatically detect. Using either Java Xmx flags (cumbersome/duplicated) or the new experimental JVM flags we can solve this issue.
Docker love for Java is in its way in newer versions of both OpenJ9 and OpenJDK 10!
Mismatch in virtualization
The combination of Java and Docker isn’t a match made in heaven, initially it was far from it. For starters, the whole premise of the JVM, Java Virtual Machine, was that having a Virtual Machine makes the underlying...
In a microservices landscape; When do you update?
This week I’ve been stuggling with the following question:
When is the right time to upgrade?
By upgrading, I mean everything: libraries, tools, Java versions, application servers, MQ servers…
My current project uses a reactive upgrade policy, we upgrade for four reasons:
- Something is broken and fixed in a later version
- We need or want to use a new feature
- Support for a version we’re using is being dropped
- The old version we’re using has a known security issue/CVE
The first two reasons are entirely up to the programmers to decide. The third reason is up...
Fear of upgrading to Java 9, is it justified?
It seems that the adoptation of Java 9 is slow, very slow. In a Twitter poll this week I asked: “Which version of Java are you using in production?”
The poll got almost 300 replies and to my surprise just 3% of the respondents are using Java 9 at the moment. Most are using Java 8 and there are even more people using Java 6… So what is holding people back? Why is almost no-one using Java 9?
It turns out a lot of people are scared to upgrade to Java 9. They think it’ll be hard to do,...
Inverse Conway's law
Today I got to present at Devoxx Poland on being agile and managing your architecture.
One of the points I made during the talk had to do with Conway’s Law. For those unfamiliar with it, here it is:
organizations which design systems … are constrained to produce designs which are copies of the communication structures of these organizations M. Conway
This basically means that the code you create is likely to reflect the way the people and teams in your company communicate. For example, banks are usually pretty strict and have a tendency to document things. The...
JavaOne Rock Star 2016
Today I got an email with the subject: “Congratulations JavaOne 2016 Rock Star!”. It turns out the JavaOne 2016 Ignite session was voted enough to receive a JavaOne Rock Star Award!
I was so excited, elated even!
But I quickly found out that the JavaOne Rock Star lifestyle isn’t as much fun as it sounds.
- Being 3 hours late for a meeting, even a Rock Star can’t do that.
- Peeing in the corner of your office while holding a bottle of Jack Daniels, still not appreciated.
- Wearing ripped jeans, a leather jacket...
Vikipedia: A Java YouTube bot
YouTube, the future of television. I’ve got a lot of subscriptions to YouTube channels that deliver quality content, and those shows are ‘cast’ (using my Chromecast) to my TV. Another thing I often do is look up information, for example I watch talks from programming conferences like Devoxx using YouTube.
This gave me an idea, what if I can take some free information (like Wikipedia, all creative commons) and use that to create content for YouTube? Maybe I’ll even get some views :-)
So this is what I’ve come up with, the following video is generated completely automatically:
Three new JEPs
This morning Mark Reinhold submitted three brand new JEPs (JDK Enhancement Proposal).
- JEP 300: Augment Use-Site Variance with Declaration-Site Defaults
- JEP 301: Enhanced Enums
- JEP 302: Lambda Leftovers
These proposals are enhancements to the JDK (Java Development Kit) and OpenJDK. A long term roadmap for the JDK projects, a look into what the future of Java might hold.
Let’s dive right in and take a quick look on what these proposals actually are!
JEP 300: Augment Use-Site Variance with Declaration-Site Defaults
When you currently use Java Generics you probably already know about wildcards....
Excuse me, sorry to interrupt...
Interruptions are a software developers worst nightmare. This is what you often hear. There is nothing worse than being interrupted while working hard on a problem, while you’re in the zone. You’ll lose your train of thought and the world collapses.
The idea is that in software development you are sometimes very deep into a problem, analysing code:
This orchestrator calls that service, it is managed by this class and talks to that queue. So this generator has these parameters and it all depends on… “hey I still need your time sheet”
Poof… everything gone....
JavaOne 2016, the Future of Java EE
Lately there has been a lot of rumor going around about the future of Java EE. Oracle ex-employees Reza Rahman was one of the first to voice their concern about Java EE. It seemed that all development on the seperate JSRs (Java Specification Requests) that make up Java EE 8 ground to a halt and Oracle was thinking about stopping Java EE development all together.
Oracle finally gave some insight on their proposal of the future of Java EE during JavaOne 2016 (where I am right now).
What is Java EE?
First, lets take a step back...
Job titles when writing code
The company I work for (JPoint) we don’t have work titles. Well, we do, but you’re free to pick one. Some people call themselfs ‘software developer’, some are having more luck as ‘software architect’, others label themselfs as ‘software craftsman’ and there might be a ‘software ninja/rockstar’ hanging around.
But I have a problem with that… all those terms don’t reflect on what we do. Currently I’m sitting in a session at JavaOne and I’m having the feeling people don’t realize what their job actually is.
#So, what does a software coder do?#
When creating software we instruct...
Saving the world with a code review
This morning I noticed the following tweet by fellow programmer (and runner) Arun Gupta:
Why code reviews are important? pic.twitter.com/8KyMo7Syis
— Arun Gupta (@arungupta) August 28, 2016
The tweet contained the following cartoon by ‘Oppressive Silence’, check out their website for more laughs!
(Solved by a code review?
The main question I’d like to ask:
Is this really something that you’ll find during a code review?
I think my answer below won’t surprise you, but...
Gender (in-)equality: my honest mistake
Gender equality and discrimination in IT is a hot topic. More and more women are (rightfully) opening their mouth and point out problem areas. There are just some men who just don’t get it, those insensitive idiots, they are the reason IT is such a toxic harsh environment for women.
So I thought…
This is a story about when I realized I am (unintentionally) one of those idiots.
Joy of Coding
This friday I spoke at Joy of Coding in Rotterdam. An awesome conference and a real example for other conferences regarding gender equality. The main organizer is...