Microsoft uses Java extensively inside the company across various products and services, including Azure, SQL Server, Yammer, Minecraft, and LinkedIn. It also has more than a thousand developers building apps for Android who rely on Java. So, it shouldn't be too surprising that Microsoft is making its own Java development kit available to customers, as well.
On April 6, Microsoft is rolling out a preview of the Microsoft Build of OpenJDK, a long-term support distribution of the OpenJDK. It includes the binaries for Java 11 and is available on x64 server and desktop environments on Windows, as well as on MacOS and Linux. Microsoft also is publishing today a new early-access release for Java 16 on Windows on Arm. (Last June, Microsoft's Java Engineering Group announced it had completed the first phase of porting OpenJDK for Windows on Arm.)
Microsoft bought jClarity in 2019 with the stated intent of using its technology to optimize Java workloads on Azure. jClarity touted its commercial support for AdoptOpenJDK binaries as being "the drop-in replacement for Oracle's Java/JDK." Microsoft has been a sponsor of the AdoptOpenJDK project since 2018. The company's jClarity purchase kicked off the official formation of the Java Engineering Group in Microsoft's Developer Division, officials said.
According to company officials, Microsoft currently deploys more than 500,000 Java Virtual Machines internally (excluding all Azure services and customer workloads) for back-end microservices, big data systems, message brokers, streaming services, and gaming servers. More than 140,000 of these JVMs are already based on the Microsoft Build of OpenJDK.
The packages and installers for Microsoft's OpenJDK preview build are available here. Microsoft Azure customers also can try out the preview using Azure Cloud Shell in their browsers or the Windows terminal.
Later this year, the Microsoft Build of OpenJDK will become the default distribution for Java 11 across Azure-managed services, officials said.
"Customers won't have to perform any maintenance tasks, as the transition will be smooth and transparent through application deployments," today's blog post says. "For all other Azure services, customers can bring their JDK of choice including Microsoft Build of OpenJDK."
Microsoft's OpenJDK preview release comes a day after the US Supreme Court ruled that Google could legally use Oracle's Java API code when building Android.