OpenJDK or Java on Linux

From scraping or verifying data with Java to using machine machine learning to build weather forecasting software, these days you can teach yourself just about anything with a decent online tutorial. Yet still, first-time Linux users continue to struggle with installing the software on their machines.

The truth is that installing software on Linux only looks complicated because we are so accustomed to the Windows operating system method.

StatCounter, a global collector of statistics related to computers, estimates that only 1.93% of all computers run on a traditional Linux operating system, which means that most of the world, understandably, would likely have a hard time getting used to installing software their first time around. That’s probably where Linux gets its unapproachable reputation.

Since Linux is a favorite of programmers who enjoy working on their own software projects and computer security gurus, Linux users will likely want to install Java on their machines. Read on in this tutorial to find out more about Java, or OpenJDK, and how to install it on Linux.

What is OpenJDK?

OpenJDK is the Open Java Development Kit created by Oracle. It's the open-source implementation of the Java SE Platform, which deploys network enterprise programs. It’s free to download and make changes to. There are 12 versions, but version 11 is the most current as version 12 is still being stabilized.

OpenJDK is the open-source version of Java's developer environment, which has its own Java Runtime Environment. It's more advanced than the previous Java Runtime Environment (JRE) because it contains all of the tools necessary to create Java applications.

OpenJDK includes a virtual machine called HotSpot, which is a virtual machine for servers and standard computers. This element allows developers to try out new software builds.

It also includes the full Java Class Library, which is a set of libraries that run in the virtual machine that developers call to assist with a variety of features. OpenJDK also includes javac, the Java compiler.

OpenJDK vs. Oracle JDK

If you’re familiar with OpenJDK, you’ve likely heard of Oracle JDK. You might wonder what the
difference is between OpenJDK and Oracle JDK and why Oracle has two different pieces of
software that seem quite similar.

OpenJDK has new releases every six months, approximately, while Oracle JDK only comes out
with a new edition once every three years. This difference in release schedules also comes with
different support—OpenJDK has short-term support, only until its newest release, while Oracle
JDK offers years-long support.

Other than these differences in support and release schedules, there is not much of a difference
from a software perspective. Oracle JDK was designed after OpenJDK and modeled on it,
which explains its similarities.

The two do contain different features, however. Oracle JDK contains Mission Control and Flight
Recorder, along with data-sharing features. Oracle JDK also differs in its trash removal features
and rendering capabilities. OpenJDK, for its part, offers a font renderer feature that Oracle JDK
does not have.

Finally, in terms of popularity and development capabilities, the two each have their own
strengths. Oracle JDK is developed directly by Oracle, while OpenJDK is an open-source
collaboration between Oracle, Java's community contributors, and other major companies like
IBM, Red Hat, and Apple.

So while Oracle JDK is more stabilized thanks to its single developer, OpenJDK has major tech
players contributing to its features and adding new elements with each update. Its more
frequent updates also give it the advantage of constantly having up-to-date capabilities, more in
line with other software.

Oracle JDK is also more widely used by companies that use Java development software, but
there are many large-scale Ubuntu distributions that pre-install OpenJDK as a default.

Why Linux Requires Special Installations

Installing software the Windows or Mac way means downloading an application or piece of
software from the internet or app store and running an installation wizard to put it on your
computer. It’s straightforward, but most users don’t know what’s going on behind the scenes of
each of those pieces of software they’re downloading.

Linux, on the other hand, is much more hands-on, and that’s the way Linux users like it. It’s not
that installing software on Linux is more difficult, it’s that it’s different than what most computer
users are used to doing.

Instead, users must visit software repositories on their distribution to download their software
and interact with the command line to unpack it. But from there, Linux users are granted access
to much more software than their Windows and Mac counterparts.

The other issue that Linux might present for new users is that there are multiple different Linux
distributions. Each distribution comes with its own perks and disadvantages. Some distributions
can be as different as using two different operating systems entirely.

Install Java Linux

To install OpenJDK on Linux, you’ll first start by downloading and extracting the archives to read
about the installation specifications for your chosen version of OpenJDK. To open JDK 11, for
example, you’ll enter the following into your command line:

$ tar xvf openjdk-11*_bin.tar.gz

This opens the archive for your selected version. Next, you'll enter the command to open and
install your OpenJDK version. Again, using version 11, you can use the following code:

sudo apt-get install openjdk-11-jdk

Note that the above command uses sudo. You should always use caution when using sudo
commands as they don’t require root passwords to make significant changes to your system, so
they could pose a security risk if you’re not careful.

Using OpenJDK on Linux

OpenJDK is an extremely powerful software development tool, particularly when paired with a
Linux machine. Developers can use it to create new projects, particularly with the help of the
HotSpot virtual machine feature, which provides the ultimate software testing environment.

Conclusion

If it's your first time installing software on a Linux machine, the process can be confusing. But the way Linux's software installations work—in a much more hands-on way—is a more rewarding way to work with software.

Installing OpenJDK on your Linux machine will allow you to work directly with Java applications and maybe even develop some of your own. OpenJDK encourages experimentation and development and is well worth installing on your Linux machine.