How to install a specific JDK on Mac OS X

For every Java developer working on Apple’s powerful ecosystem, knowing how to install a specific JDK on Mac OS X is a fundamental skill. Whether you’re building a cutting-edge application, maintaining an older project, or simply exploring the vast possibilities of the Java Development Kit, having the correct version installed is paramount. This guide will walk you through various methods, ensuring you can confidently manage your Java environment, from setting up essential environment variables to utilizing powerful package managers. We’ll delve into the nuances of different Java versions, explore the convenience of tools like Homebrew and SDKMAN!, and provide clear instructions to streamline your development process on macOS. Properly configuring your JDK isn’t just a technical step; it’s a critical foundation for efficient and error-free software development.

Understanding JDK, JRE, and JVM on macOS

Before diving into installation specifics, it’s crucial to differentiate between the core components of the Java ecosystem. The Java Development Kit (JDK) is a software development environment used for developing Java applications. It includes the Java Runtime Environment (JRE), an interpreter/loader (java), a compiler (javac), an archiver (jar), and other tools needed for Java development. The JRE, in turn, contains the Java Virtual Machine (JVM), which is responsible for executing Java bytecode. For developers, the JDK is the essential package, as it provides all the necessary tools to compile, debug, and run Java code.

On macOS, various Java versions coexist, each tailored for different project requirements. For instance, Java 8 (LTS) is still widely used for enterprise applications due to its stability and extensive library support, while newer versions like Java 17 (LTS) or Java 21 (LTS) introduce modern features and performance enhancements. Understanding which specific JDK your project requires is the first step in a successful installation. Using an outdated or incorrect Java version can lead to compilation errors, runtime issues, or compatibility problems with frameworks and libraries. Therefore, careful selection of the right Java Development Kit is not merely a preference but a technical necessity for robust software development.

Preparing Your Mac for JDK Installation

Before installing a new JDK, it’s good practice to assess your current Java landscape on your Mac. You can check if Java is already installed and which versions are present by opening your Terminal application and typing java -version and /usr/libexec/java_home -V. The latter command lists all installed Java versions and their paths, which is incredibly useful for managing multiple installations. This initial check helps prevent conflicts and ensures you’re aware of any existing configurations that might influence your new installation.

A key aspect of preparing your system involves understanding environment variables, especially JAVA_HOME and your system’s PATH variable. The JAVA_HOME variable points to the root directory of your active JDK installation, enabling various build tools and applications to locate the correct Java runtime. The PATH variable, on the other hand, tells your shell where to find executable commands like java and javac. Incorrectly configured environment variables are a common source of “Java not found” errors or unexpected behavior. Experienced developers often manage these settings within their shell configuration files, such as ~/.zshrc or ~/.bash_profile, to ensure consistent access to their preferred Java versions.

Method 1: Installing JDK via Homebrew (Recommended)

For most macOS users, Homebrew stands out as the most convenient and efficient method for installing and managing software packages, including specific Java Development Kit versions. Homebrew simplifies the process by handling dependencies and ensuring proper file placement, making the installation of JDK on Mac OS X straightforward and less prone to errors. If you don’t already have Homebrew installed, you can do so by running /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)" in your terminal. This command downloads and executes the Homebrew installation script directly from its official repository, a trusted source for macOS package management. According to a recent survey by Homebrew, it’s used by millions of developers worldwide, attesting to its reliability and widespread adoption.

To install a specific JDK using Homebrew, you typically use the brew install command with the appropriate OpenJDK formula. For example, to install OpenJDK 17, you would run brew install openjdk@17. Homebrew often symlinks the installed JDKs into a managed directory, but you might still need to set your JAVA_HOME environment variable manually to point to the correct version, especially if you have multiple JDKs. This often involves adding a line like export JAVA_HOME="/usr/local/opt/openjdk@17/libexec/openjdk.jdk/Contents/Home" to your shell configuration file (e.g., ~/.zshrc or ~/.bash_profile) and then sourcing the file (e.g., source ~/.zshrc). This ensures that all applications and your terminal session correctly recognize the desired Java version.

**To quickly install a specific JDK on Mac OS X using Homebrew, first ensure Homebrew is installed. Then, use Question & Answer :
I want to install a specific JDK (the latest for example). For this, I went to the JDK download homepage: http://java.sun.com/javase/downloads/index.jsp. I looked for a Mac version, but I’m a bit surprised to only see downloadable versions for Linux, Windows and Solaris…

Here’s the message for Mac:

> “Apple Computer supplies their own version of Java. Use the Software Update feature (available on the Apple menu) to check that you have the most up-to-date version of Java for your Mac.”

OK BUT… when I update Java with Mac I have a JRE and not a JDK…

I don’t understand why a JDK version doesn’t exist that is easily downloadable/installable (like a jar to unzip?) for Mac…

In a comment under @Thilo’s answer, @mobibob asked how to set JAVA_HOME in your .bash_profile on a Mac. Answer:

export JAVA_HOME=`/usr/libexec/java_home` 

This will dynamically assign to JAVA_HOME the location of the first JDK listed in the “General” tab of “Java Preferences” utility.

See Apple Technical Q&A 1170: https://developer.apple.com/library/content/qa/qa1170/_index.html

EDIT:

If you prefer parentheses to backticks for command substitution, this also works:

export JAVA_HOME=$(/usr/libexec/java_home) 
```**