Shaaf's blog

A technical blog about Java, Kubernetes and things that matter

Java monitoring: Exploring Cryostat 2.4 features on OpenShift

Orignally posted at Red Hat Developers

Red Hat’s latest build of Cryostat 2.4, designed specifically for the Red Hat OpenShift Container Platform, brings a wealth of features and enhancements that cater to various monitoring needs for Java applications.

At its core, Cryostat 2.4 excels in comprehensive Java Flight Recorder (JFR) data management. Users can effortlessly start, stop, retrieve, archive, import, and export JFR data, all through an intuitive web console or an accessible HTTP API. This enhances the ease with which developers can handle JVM performance data. Moreover, Cryostat 2.4 provides flexibility in terms of data storage and analysis. Users can store and analyze JFR data directly on their Red Hat OpenShift or export it to external monitoring applications for a deeper dive into the data.


Whats New for developers in JDK 21

Orignally posted at Red Hat Developers

In an exciting development for Java developers, this September 19th marked the release of JDK 21. This release contains many new capabilities that benefit the Java ecosystem, including virtual threads, record patterns, and sequenced collections. There are also some interesting features in the preview for JDK 21, such as string templates, scoped values, and structured concurrency. This article highlights six new features in this release.


error: --enable-preview must be used with either -source or --release

The JDK 21 release is well underway likely to drop around September 19th, and its not GA yet. further more it provides preview features.

It was time for downloading one of the releases and giving it a try. Well I have given it a try some weeks ago so I already had it installed. e.g.

openjdk version "21-ea" 2023-09-19
OpenJDK Runtime Environment (build 21-ea+26-2328)
OpenJDK 64-Bit Server VM (build 21-ea+26-2328, mixed mode, sharing)

The fun thing though is that there are couple of very cool features that are still in preview. e.g. I tried to use the StringTemplates mentioned in the InfoQ blog


Processing images in Java with OpenCV and Quarkus

If you are into Computer vision, you probably are familiar with OpenCV. Its an amazing library that has almost everything one needs to do 2D and 3D processing and much more. Gesture recognition, face detection, Motion tracking, think of anything related to image processing and OpenCV can be your goto. Its based on the BSD license, so you can just download it and start using it.

OpenCV is written in C, and there are nice Java bindings for it too. If you are a Java developer like me and dont want to get into all the loading and building native bindings etc., then read on. In this article I will show how you can use OpenCV with the popular new framework Quarkus, without worrying about installing libraries or reloading the entire app.


SQL cache stores and more in Data Grid 8.3

Orignally posted at Red Hat Developers

Red Hat Data Grid is a distributed, cloud-based datastore offering very fast response times as an in-memory database. The latest version, Data Grid 8.3, features cross-site replication with more observability and two new types of SQL cache store for scaling applications with large datasets. This version also brings improved security, support for Helm charts, and a better command-line interface (CLI).

This article is an overview of new features and enhancements in this latest version of Red Hat Data Grid.