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Installing JDK

We will cover the installation procedure of Oracle's implementation of JDK 8 only. If you have already installed a JDK implementation that is fully compatible with the Java SE 8 platform, including the open source OpenJDK 8 or IBM's J9 JDK 8, then generally, it should work fine and you can skip this section.

Not all features discussed in this book are available in non-Oracle JDK implementations. When applicable, we will mention exceptions.

On each operating system, an environmental variable, namely JAVA_HOME, must be created that points to the installation directory of JDK (or JRE on non-development computers). For the operating systems covered in this book, (Windows, macOS, and Linux) instructions are provided on how to do this. Many important JVM tools require this variable. Applications that require this include build tools and application servers. We will provide instructions for the following topics:

Downloading JDK
Installing JDK on Windows
Installing JDK on macOS
Installing JDK on Linux
Downloading the Javadoc API documentation