Microsoft is set to make its own distribution of Java the default across its Azure cloud services. The firm has unveiled a preview of its own build of OpenJDK, the open-source implementation of Java, and said it already has 140,000 JVMs operating internally using the code.

Announcing the preview on its Java blog, the software giant said the Microsoft Build of OpenJDK will be a Long-Term Support (LTS) distribution of OpenJDK that is open source and available for free for anyone to deploy anywhere. This release is based on Java 11 and includes binaries for server and desktop environments on Macs, Linux, and Windows, plus an Early Access binary for Java 16 for Windows on ARM.

However, Microsoft said it plans to release OpenJDK 17 binaries by the end of this year, once Java 17 is finalised. Support for Java 11 will be available until at least 2024.

This release of the Microsoft Build of OpenJDK is a preview to allow customers and users to provide feedback on issues like the packaging and installation experience before a production-ready release is made generally available.

Microsoft said its binaries for Java 11 have passed the Java Technical Compatibility Kit (TCK) for Java 11, and that its build of OpenJDK is a simple drop-in replacement for any other OpenJDK distribution.

Although seen as less glamorous than some developer languages, Java is still one of the most widely used. Microsoft has said that it relies on Java technologies for a variety of its own internal systems, applications, and workloads to enable many of its public services and products, as well as a significant set of mission-critical systems that power Azure infrastructure.

The Azure platform is also seeing significant growth in Java workloads through Azure Spring Cloud, Azure App Service, Azure Functions, and Azure Kubernetes Service, Microsoft claims. As a result, the Microsoft Build of OpenJDK is set to be made the default distribution for Java 11 across Azure-managed services later this year.

On Azure-managed services that offer Java 8 as a target runtime option, Microsoft will be supporting Java 8 binaries from Eclipse Adoptium. However, Microsoft said it recommends that customers move to Java 11 and later versions in order to benefit from enhancements that translate into cost savings in cloud deployments and accelerated developer productivity. The company provides guidance to help streamline this transition.