The worker tries to find an intersection of those paired containers (see Img.1. Those two containers each hold their own collection of numbers. The idea of this simple app is to have two “containers” held by the individual "worker". This means any detailed platform configuration is avoided as the goal is to compare basic platform configuration. The application Threads are also reduced in both cases in order to -again - obtain comparable results. Such events wrap equivalent sections of the application (Java/Kotlin) to obtain comparable results. We used the following 2 examples to get some measurable data:Įach example uses similar JMC/JFR Events. Įach measurement is done in a 45 seconds time window.
For each measurement we use the current development state of the JMC/Java Flight Recorder - Early Access. Let’s now compare the characteristics of a comparable Java & Kotlin app using the JMC/JFR! First, we share the setup. An example of such an issue is the well-known NPE (Null Pointer Exception). Such constructs can help teams move faster without causing unwanted issues. But nonetheless Kotlin has many nice constructs ( an usage of when-smart-casting or type references). I have put the word "benefits" in the previous paragraphs between apostrophes intentionally as some nice concepts may look very neat in Kotlin, but they may not be as optimized as Java’s counterpart (considering latest Java builds)! The Java Ecosystem evolves pretty fast and Java stays the 1st JVM language and also the most optimized one. This is also out of the scope of this article. The reason for this may seem obvious,but there are different perspectives for this choice and a discussion about it may turn into chicken-egg arguments. Perhaps because of these often spelled Kotlin "benefits", nowadays more companies are thinking about or are already using a Kotlin stack for backend development. It offers a set of quite handy features and traits such as: data classes, concise, safety, smart casting, functional capabilities etc. In short, Kotlin is an object-oriented statistically typed language.
OPENJDK 7 JVM INTERNALS ANDROID
Kotlin has since been successfully adopted by the Android community and is gaining ground on the backend as well. The communicated goal was to become a “better language” for the JVM. It was introduced in 2011 as a new language for JVM and has been developed by JetBrains. Kotlin belongs to the JVM language family. I would even bet a couple of million articles have already been written about Java, so it’s fair to have just a short Kotlin introduction. Let’s briefly introduce Koltin first as Java has been around for quite a while.
OPENJDK 7 JVM INTERNALS CODE
The purpose of this article is to compare a Kotlin and a Java app and touch “hidden” compiled code compositions. The letters JFR stand for the Java Flight Recorder, which is an event-based toolset build directly into the JVM.Įxciting, isn't it? The JFR can provide a view to the JVM internals through emitted events and more… All good so far, but what is the JMC/JFR? JVM supports all languages that are able to be compiled into the Java byte-code. The JVM enables a computer to run Java programs, but not just that. Starting slowly: what is the JVM? The JVM stands for Java Virtual Machine. The exact answer to this question is out of the scope, but we can show what possibilities there are for understanding and measuring the behaviour of an application in regard to these aspects based on simple examples using the JFR.
OPENJDK 7 JVM INTERNALS HOW TO
Nowadays the IT world often spells terms like SRE ( Site Reliability Engineering) or latencies, but how to measure this in an accurate way without relying on “random” samples. The goal of this article is to examine the possibilities of profiling a Kotlin and a similar Java application with JMC/Java Flight Recorder to get a better understanding of their behavior compared to each other. It's a very interesting subject that deserves definitely more attention. This article is inspired by the JUG talk I gave about utilising Java Flight Recorder to profile Kotlin applications deployed into the cloud.