Open-source Java has long been an important part of the Java ecosystem, but over the past few years more and more companies are moving from commercial distributions to open-source ones. 

The move away from Oracle’s distribution has been quite significant. In fact, a 2022 New Relic survey found that Oracle’s share of the Java market had dropped from 75% in 2020 to 35% in 2022.

There are many alternatives —  both commercial and open-source — to the standard Oracle distribution, and in 2017, the Adoptium project (at the time it was called AdoptOpenJDK) was formed to promote high-quality builds of OpenJDK. The build provided by the Adoptium project is called Eclipse Temurin. 

According to the Eclipse Foundation and the Adoptium Working Group, in February 2023 there were over 12.3 million downloads of the Eclipse Temurin binaries, which is more than double what it had been the same time the previous year. 

“I think that really that growth year-over-year indicates the traction that it is getting amongst developers and enterprises that are looking for a robust, secure, high quality Java runtime,” said Mike Milinkovich, executive director of the Eclipse Foundation. 

Eclipse Temurin is now the default Java option in GitHub Actions, which may be contributing to increased uptake as well. It’s also used in a number of container images, and the working group sees participation from major organizations like Bloomberg, Google, IBM, and Red Hat. 

The Eclipse Foundation speculates that Oracle’s licensing structure changes may be contributing to the increased interest as well. According to Tim Ellison, PMC lead for Eclipse Adoptium, the commercial versions now amount to a pretty significant part of the IT budget. 

“We need to make sure that there are robust alternatives and viable alternatives to that paid-for product,” said Ellison. “We can get that at a lower cost by supporting the open source communities that are producing a drop-in replacement and the direct replacement for that.”

Aside from the economics, the increased interest may also be an indicator that the open source community is building something better than the commercial offerings. 

“All of these very large companies are coming together, pooling their resources, and getting a multiplier effect on the downstream binary, which is a standardized product kind of by definition. “[And leads to a better product] for Java than any individual vendor can do,” said Ellison.