How to Install Java JDK on MacOS

Introduction

The Java Development Kit (JDK) is an essential tool for developing Java applications, and installing it on macOS is a straightforward process. While specific JDK versions may vary, the steps for downloading, installing, and configuring the JDK remain largely the same across different versions. This guide will walk you through the process of installing the JDK on macOS, ensuring that your system is ready for Java development.

Step 1: Download the JDK

To begin, download the appropriate version of the Java JDK for macOS from the official Oracle or OpenJDK website. To do so, follow the appropriate steps

1. Visit the Download Page
   Navigate to the Oracle JDK downloads page or OpenJDK.
2. Select the Version
   Choose the version of the JDK that you want to install. Common versions include JDK 8, 11, and 17. If you’re unsure, it’s generally a good idea to choose the latest Long-Term Support (LTS) version.
3. Download the macOS Installer
   • Look for the macOS option, typically marked as .dmg or .pkg, depending on the JDK distribution.
   • Download the correct version based on your system architecture (macOS versions for Intel or Apple Silicon/ARM processors are typically available).

Be sure to download the correct installer for your machine’s architecture to avoid compatibility issues (see Additional Notes below for more details).

Step 2: Install the JDK

Once the download is complete, follow these steps to install the JDK on your macOS system.

1. Open the Downloaded File
   Double-click the .dmg or .pkg file you downloaded. This will mount the disk image or start the package installer.
2. Run the Installer
   Follow the instructions in the installation wizard. This will guide you through accepting the license agreement and selecting the installation destination (usually /Library/Java/JavaVirtualMachines/ by default).
3. Complete the Installation
   Once the installation is finished, the JDK will be installed on your system.

Step 3: Configure Environment Variables

After installation, you need to set the JAVA_HOME environment variable and update your system’s PATH to use the JDK from the terminal.

1. Open Terminal
   Use Spotlight (Cmd + Space) to search for Terminal or open it from the Applications > Utilities folder.
2. Set the JAVA_HOME Variable
   • To set JAVA_HOME for your current session, type the following command:

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

   • To make this setting permanent, add the command to your shell profile file. For example, if you’re using the Zsh shell (which is the default on macOS since version 10.15 Catalina), you can add the following line to the ~/.zshrc file:

     echo 'export JAVA_HOME=$(/usr/libexec/java_home)' >> ~/.zshrc
     

   • For older systems using Bash, add the line to the ~/.bash_profile file:

     echo 'export JAVA_HOME=$(/usr/libexec/java_home)' >> ~/.bash_profile
     

3. Update the PATH Variable
   • Add the JDK’s bin directory to your PATH so you can run Java commands from any terminal session. You can do this by adding the following line to your shell profile file (either ~/.zshrc or ~/.bash_profile):

     export PATH="$JAVA_HOME/bin:$PATH"
     

4. Apply the Changes
   To apply these changes without restarting your terminal, run:

   source ~/.zshrc   # or source ~/.bash_profile for Bash users
   

5. Verify that JAVA_HOME Is Set Correctly

   echo $JAVA_HOME
   

   The output should show the path to your JDK installation, something like /Library/Java/JavaVirtualMachines/jdk-21.jdk/Contents/Home.

Step 4: Verify the Installation

To verify that the JDK is correctly installed and configured, open a terminal and run the following commands:

1. Check the Java Version

   java -version
   

   You should see output similar to this, confirming the installation of JDK:

   java version "21"
   Java(TM) SE Runtime Environment (build 21+35-2431)
   Java HotSpot(TM) 64-Bit Server VM (build 21+35-2431, mixed mode)
   

2. Check the Java Compiler (javac)

   javac -version
   

   This will confirm that the Java compiler is available and working.

If both commands return the expected version numbers, your Java JDK installation is complete.

Additional Notes: Apple Silicon (ARM) vs. Intel

macOS systems now come with either Intel or Apple Silicon (M1/M2) processors. When downloading the JDK, be sure to choose the version that matches your system’s architecture:

• Intel Macs
  Most macOS systems prior to 2020 are powered by Intel processors. If you’re using an Intel-based Mac, select the Intel version of the JDK from the download page.
• Apple Silicon (M1/M2/…)
  Newer Macs (released from 2020 onward) use Apple’s ARM-based Silicon processors. Be sure to download the JDK version specifically built for Apple Silicon. Many distributions, including Oracle JDK and OpenJDK, now provide dedicated builds for Apple Silicon to optimize performance.

If you’re unsure which version to download, you can check your processor type by clicking on the Apple logo in the top-left corner of your screen, selecting About This Mac, and reviewing the Processor section.

Conclusion

You’ve successfully installed JDK on your MacOS. You are now ready to develop and run Java applications using the latest version of the JDK. Remember to keep your JDK up to date to benefit from the latest features and security updates.

Happy coding!