openjdk

Java in a Nutshell is the ultimate reference guide for developers, with examples that show how to take advantage of modern Java APIs and best practices.

Learn about my recommendation for updating OpenJDK images since Docker Hub's deprecation announcement and how to implement this change.

Dive into how the HotSpot JVM improves your Java application's performance by eliminating range checks and cleverly optimizing loops.

Find out what Mandrel is and what it's not, in this introduction to Red Hat's downstream distribution of GraalVM for Quarkus and other projects.

Find out how Red Hat engineers and a community of open source enthusiasts created the standard OpenJDK implementation for AArch64.

Install Red Hat's migration toolkit for applications on your Windows, macOS, or Linux laptop, then get started using it in your favorite browser.

You can now use OpenJDK's JDK Flight Recorder to collect custom events. Learn how to use JDK Mission Control agents with JFR's Event API in your Java code.

Don't let long load times bog down your Java applications! Learn how to use Checkpoint/Restore in Userspace (CRIU) for faster startup with checkpoints.

Learn how Migration Toolkit for Applications 5.0 analyzes your VM-based Java applications and helps you migrate them to containers.

Learn how to troubleshoot, monitor, and profile your container-based Java applications with JDK Flight Recorder, courtesy of OpenJDK 8u 262.

Discover how GraalVM adding DWARF debug information to its Linux images enables effective source-level Java-native image debugging through gdb.

Learn how Quarkus team, production users, and the community drove Quarkus to a full GA product available in Red Hat Runtimes and what's new in this release.

Explore where Quarkus fits in the Kubernetes-native Java ecosystem for faster microservices and serverless applications, and walk through an example.

Oracle has stopped providing free long-term JDK update binaries to commercial users; Andrew Haley explains Red Hat's role in filling the gap.

Quarkus allows a comprehensive and seamless approach to generating an operating system specific (aka native) executable from your Java code.

JDK Mission Control is the newest member of the Red Hat Software Collections. Give it a try with the Red Hat Build of OpenJDK in this tutorial.

How to build a Java 8 runtime image with Docker and also with Buildah. Deployment to OpenShift is also shown by pushing the image to Quay and importing the stream.

How to use Red Hat Application Migration Toolkit to analyze you codebase to understand the impact of migrating to OpenJDK.

What you need to know to migrate from Oracle JDK to OpenJDK on RHEL, the impact to developers and ops teams, and solutions to potential challenges.

This post describes the furture support for Java and OpenJDK updates, now that Oracle has announced that soon it will no longer supply free binaries for JDK releases or write patches for bugs.

A user guide of Java Class Metadata. I presented a talk last week in the Free Java Room at FOSDEM 2018 on the subject of Java Class Metadata, explaining what it is, why it helps to know about it, what you might do to measure it, and reduce the impact of it's footprint on  your Java application.

In this session from the 2012 Red Hat Summit, Andrew Cathrow, product manager, and Chuck Dubuque, product marketing manager for Red Hat Enterprise Virtualization. They discuss Red Hat virtualization, including Red Hat Enterprise Virtualization 3, and the past, present, and future of virtualization technology. Dubuque discusses the current environment, including virtualization competitor VMware, and the opportunity that a second source for virtualization--a open standards source--offers. He then offers details about Red Hat Enterprise Virtualization, including information about management features, hypervisor technology, specVIRT success, and opportunities for cost savings. Cathow then joins in to talk about development of Red Hat Enterprise Virtualization 3 and 3.1, and the growth of the communities surrounding it, including Fedora and oVirt. Cathow highlights features and changes in Red Hat Enteprise Virtualization, including: - OpenJDK requirement for proprietary Oracle JRE is eliminated. - Support for Jasper 4.7 and two new directory servers - Scalability to 160 Virtual CPUs per VM and 2T virtual RAM per VM - enhanced physical to virtual migration (P2V) - Live snapshots - Shared disks - SDK availability - new top-level manager for managing disks - direct LUN access Cathow details many other system and version features, including a overview of key technologies for future versions of Red Hat Enterprise Virtualization and Red Hat Enterprise Linux. He also intermittantly takes questions from the audience. Watch more 2012 Red Hat Summit and JBoss World videos from Red Hat: http://www.youtube.com/playlist?list=PL995CD1141C3330D5&feature=plcp

Modern machines have more memory and more processors than ever. Service-level agreement (SLA) applications guarantee response times of 10 to 500 milliseconds. To meet the lower end of that goal, we need garbage collection algorithms that are efficient enough to enable programs to run in the available memory but also optimized to never interrupt the running program for more than a handful of milliseconds. Shenandoah is an open source low-pause-time collector for OpenJDK designed to meet those goals. Learn more in this session.