Choosing the Right Java JDK: Licensing & OpenJDK Distributions

In this blog, we are going to understand java JDK’s and its types, which jdk to choose, and licensing terms for JVM tools, and other openJDK distribution and lot more, Let’s begin.

Java is used everywhere from personal computers to large data centers, and we all know we use java to build client apps, such as mobile apps, desktop apps and server side, While the important point to consider is Java is not entirely or completely free to use for commercially there are some limitation, that we need to consider while using Java JDK.

What is Java JDK ?

JDK stands for “Java Development Kit”. It is a distribution of the Java language that we install in our PC to run java and execute, The high level component that is present on JDK is:

• javac (compiler (it converts our source code into bytecode .class))
• JRE (Java Runtime Environment it consists of JVM (convert the bytecode into platform specific machine code), Class Loader, and Class libraries).

Types of Java JDK build?

While Oracle provides JDK 21, Oracle JDK 17 and later, they are licensed under the Oracle No-Fee Terms and Conditions License, which permits free use for all users and even for commercially but does not allow for redistribution.

Another important point to consider is, if you want to download Oracle JDK 11 and Oracle JDK 8 that is currently licensed under the Oracle Technology Network License Agreement OTN that has end of support now, you will need to buy their commercial support (Paid subscription) if you want to use it other than this if you only use this for personal use, testing prototyping that is free at no cost.

Also, Oracle JDK is not long LTS (Long-Term-Support), which means if some JDK is labeled as Oracle JDK LTS Version ex: 17, 21, that means. This is only support for 2 years. If you want a long LTS, you will need to pay for it and other jdk version that is not labeled as an LTS. It is only supported for six-months. That is the major concern for the developer. If the support time has ended, we need to download the latest version manually.

Is there any way to mitigate the problem ?

Why not, other than Oracle JDK, there was an open-source implementation of Java JDK that is OpenJDK. This is licensed under the GPL-2.0 license, initial release: May 8, 2007, two days after my birthday tho, that is same as Oracle JDK and its components, and it will ship a feature release every six months and one exemption to this OpenJDK doesn’t provide binaries or installer, But other vendor provide this with long LTS support, let’s see type of OpenJDK build offer from other vendors in a next section.

Types of OpenJDK build ?

As I already mention, Oracle JDK SE doesn’t provide long LTS support, but other vendors provide. free LTS support at no cost without premium subscription at all with TCK tests. This is because java application example software’s, IDE’s, and tools that runs on java are based on OpenJDK, not Oracle JDK, and they actively contribute to this OpenJDK. Some of them, such as: Oracle itself, Red Hat Linux, Azul (Microsoft), IBM, Apple. Let’s now see the builds that are offered by popular vendors from OpenJDK

Most of the OpenJDK builds provide LTS support!

A TCK is a suite of tests, tools, test framework, and documentation that allows an implementor of an associated Java technology specification to determine if the implementation complies with the specification.

The choice of choosing OpenJDK binary providers depends on projects and what type of support you need ex:

If your are intergrating amazon AWS in your project, the Amazon Corretto may be a good option for you or if you want to develop desktop app using JavaFx, the BellSoft Liberica may be good option for you, becuase it also contains the JavaFx SDK or if you want general JDK that is long-term-supported with TCK verified and no cost at all the Eclipse Temurin will be the good choice

• Amazon Corretto provides LTS and this is best suited if you integrate with AWS.
• Eclipse Temurin is best suited for all general purposes!
• BellSoft also provides LTS. Moreover, BellSoft Liberica also has JavaFX SDK.
• JetBrains Runtime: they use their own OpenJDK implementation in the jetbrains products such as Android Studio and IntelliJ IDEA, so their IDE’s come with JDK

What about JVM monitering tool JFR ?

JDK Flight Recorder, or Java Flight recorder JFR, is an observability and monitoring framework built into the HotSpot JVM (available on this JVM itself) that can be used for debugging and profiling applications.

Development:

The v2.0 of JFR starting from Oracle JDK 11 or OpenJDK 11, and later can be used in production without a commercial license (without subscription) as covered in JEP 328.

Conclusion

In this blog, we learned types of JDK that is available to download, and explored some of them, and we also learned its licensing terms and support, I hope this blog helps to choose the right JDK for your next project. The reason why I make this blog is that most of them are not aware of OpenJDK and its vendor implementation. They only download JDK from the Oracle main page, which is way restricted compared to OpenJDK. I hope you will like this blog. If so, don’t forget to share this with your friends and family and I will see you in the next upcoming blog.