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Amazon Corretto extends OpenJDK support

With Java among the most popular languages on AWS, Amazon spins out its own distribution of the OpenJDK open source Java implementation with long-term support that exceeds Oracle's.

Amazon's distribution of OpenJDK pledges allegiance to its vast Java developer base with longer-term support than Oracle provides for developers of its distribution.

Amazon Corretto, now in preview, is a free, multiplatform, production-ready distribution of OpenJDK, the open source implementation of Java Platform, Standard Edition (Java SE). Amazon's commitment to OpenJDK support, and to keep it free, reflects Java's popularity among AWS developers.

Commitment and free are the operative words. Amazon Corretto, which corresponds with OpenJDK 8, provides more than four years of long-term support beyond what Oracle currently provides for its distribution of OpenJDK 8. This ensures that OpenJDK support will remain free for at least that long. Oracle will end support for commercial customers using OpenJDK 8 in January of 2019 -- two months from now -- but Amazon will support Corretto until at least June of 2023, said Arun Gupta, a principal open source technologist at AWS, in a blog post.

Amazon Corretto is designed to completely replace all Java SE distributions unless developers use features not available in OpenJDK, such as the Java Flight Recorder, Gupta said. Once installed, Corretto behaves just as the system it replaced, from running command-line options to tuning parameters and monitoring.

Joshua Bloch, Java pioneer and CMU professorJoshua Bloch

Internally, Amazon runs Corretto on thousands of production services and constantly patches the technology to address performance and scalability demands. AWS will share those patches and improvements, along with bug fixes and security patches, in quarterly updates to AWS customers.

Amazon Corretto is certified through the Java Technical Compatibility Kit (TCK) to ensure it meets the Java SE standard and is currently available on Linux, Windows and macOS. It will become generally available in the first quarter of 2019 and extend availability to the Ubuntu and Red Hat Enterprise Linux platforms.

Amazon's weight shores up OpenJDK community

Java 8 is a widely adopted release, but many users have hesitated to upgrade to more recent releases because it adds a controversial and destabilizing 'modules' feature, said Joshua Bloch, a Java pioneer at Sun Microsystems who is now a professor at Carnegie Mellon University's Institute for Software Research and remains active in the Java community. Oracle JDK is licensed under Oracle's Binary Code License Agreement, which is a proprietary license, not open source.

Other companies, notably Azul, offer open source binary distributions of Java 8 with promises of future updates with Azul Zulu, but developers will benefit from the resources Amazon brings to bear with its public commitment to four years of OpenJDK support.

A lot of conservative organizations will see this and say, 'If Amazon is using OpenJDK, as well as IBM, Red Hat et al, then my last doubts are now gone.
Martijn Verburgco-leader of the London Java Community and CEO, jClarity

"I suspect this will come as a big relief to many who have staked their future on the Java platform," Bloch said.

Amazon Corretto strengthens the message that OpenJDK is a viable runtime for production use, said Martijn Verburg, co-leader of the London Java Community and CEO at jClarity, a London-based provider of performance analysis and monitoring tools for Java apps. "A lot of conservative organizations will see this and say, 'If Amazon is using OpenJDK, as well as IBM, Red Hat et al, then my last doubts are now gone.'" he said.

Amazon worked with the AdoptOpenJDK Foundation and used the organization's scripts and expertise to solve kinks in their Windows and Mac installers and improve their testing efforts with additional tests, Verburg said. He also said he anticipates that Amazon will work hard to upstream any patches.

AdoptOpenJDK has explored further initiatives with Amazon and other OpenJDK providers to assuage fears about fragmentation, Verburg said. For example, AdoptOpenJDK has an open test suite and test pipeline with upward of 60,000 tests that any binary can be put through, which could form the basis of a shared quality bar that all OpenJDK providers could meet, he said.

The name "Corretto" derives from the Italian term "caffe corretto" or "corrected coffee" in English. This is the name the Italians gave to espresso with a shot of grappa or similar liquor, which was traditionally consumed by fishermen and other laborers before a day of hard work. With the Corretto distribution of OpenJDK, Amazon is delivering its own little "correction" for Java developers, Bloch intimated.

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