why do people use Azul’s Zulu 9.0.0.15 release of OpenJDK instead of JDK downloaded from oracle.com?
In short, there is no version of Java 9 freely supported by Oracle. You can download the last free version from Oracle.
From March 2019, Oracle will only give free support for Java 12 (for 6 months). Oracle will provide free support for the latest version for the first 6 months of release. However, there are other organisations, like Azul, which provide commercially supported releases from Java 8. To get Oracle's supported releases you need to pay a subscription.
Other organisations such as AdoptJDK and RedHat have their own releases.
For more information
https://www.oracle.com/technetwork/java/javase/tech/eol-135779.html
Is this because Oracle made the JDK commercial?
The OpenJDK has been around since Java 6, but there were some differences and not a strong reason for many to shift versions.
From Java 11, the main difference between OpenJDK and Oracle Java 11 is the installer.
Hopefully, we will see more companies paying for support for the products they rely on to help make money, but also see a variety of options for free use in a secure way.
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In my job i tried to use zulu jdk days ago with a legacy project rather than Oracle-jdk but i had some issues with the glassfish version that was used. Anyway, i felt a difference in the compilation time of the project. Today i was having problems with my old machine opening eclipse with open-jdk on manjaro linux, so i gave another chance to zulu, and i'm feeling a big difference on the startup time and cpu consumption.
Anyone has a benchmark or a explanation about the technical differences of zulu?
why do people use Azul’s Zulu 9.0.0.15 release of OpenJDK instead of JDK downloaded from oracle.com?
In short, there is no version of Java 9 freely supported by Oracle. You can download the last free version from Oracle.
From March 2019, Oracle will only give free support for Java 12 (for 6 months). Oracle will provide free support for the latest version for the first 6 months of release. However, there are other organisations, like Azul, which provide commercially supported releases from Java 8. To get Oracle's supported releases you need to pay a subscription.
Other organisations such as AdoptJDK and RedHat have their own releases.
For more information
https://www.oracle.com/technetwork/java/javase/tech/eol-135779.html
Is this because Oracle made the JDK commercial?
The OpenJDK has been around since Java 6, but there were some differences and not a strong reason for many to shift versions.
From Java 11, the main difference between OpenJDK and Oracle Java 11 is the installer.
Hopefully, we will see more companies paying for support for the products they rely on to help make money, but also see a variety of options for free use in a secure way.
There are a few OpenJDK's out there. The official Open JDK and Oracle's JDK are based on the same code but have different licensing models. The main reason for creating them was to tweak some parts of the code to better handle a part of the API that you think should work differently.
For example, let's say you are a company that uses JAVA and notices that some part of the API works to slowly for your needs. You then can try to improve it and submit it to be part of the Oracle OpenJDK. But it could be rejected or the time it takes for it to be approved takes too long. You might opt to just branch the OpenJDK to make your own version.
At the moment Oracle is going to stop giving its own implementation of the JDK for free but it its version of OpenJDK will remain open and free.
If you read here you will see that Zulu too is just OpenJDK certified and promised to be maintained. My guess is that the company is just using OpenJDK to give better service to its subscribers so they will get notified when new fixes and patches become available to the general public. I don't think they change anything in the JDK but just create custom delivery tools around it.