How to Change Default Java Version on Mac

As a Mac user, you may encounter situations where you need to change the default Java version on your system. Whether it’s for development purposes, compatibility issues, or specific software requirements, knowing how to switch between Java versions can be incredibly helpful. In this blog post, we will guide you through the process of changing the default Java version on your Mac, providing step-by-step instructions and valuable insights along the way.

Video Tutorial:

Why You Need to Change Default Java Version on Mac

There are several reasons why you might need to change the default Java version on your Mac. Here are a few common scenarios:

1. Development Environment Compatibility: If you are a software developer, you may encounter situations where certain applications or projects require a specific version of Java to run or build successfully. Changing the default Java version allows you to switch between different versions based on your development needs.

2. Application Compatibility: Some older or specialized software applications may only work with specific versions of Java. By changing the default Java version on your Mac, you can ensure compatibility with these applications and avoid potential conflicts.

3. Performance and Security: Newer versions of Java often come with performance improvements and security updates. By upgrading to a newer version and setting it as the default, you can take advantage of these enhancements and ensure a safer computing experience.

Method 1: Changing the Default Java Version via Terminal

To change the default Java version on your Mac using Terminal, follow these steps:

1. Open Terminal: You can either use Spotlight Search by pressing Command + Space and typing "Terminal," or navigate to Applications > Utilities > Terminal.

2. Check Current Java Version: Type the following command in Terminal and press Enter to check the current default version of Java installed on your Mac:
`java -version`

3. List Available Java Versions: Use the following command to list all the available Java versions on your system:
`/usr/libexec/java_home -V`

4. Set the Desired Java Version: Determine which version you want to set as the default, and copy the corresponding path mentioned in the output of the previous command. Once you have the path, use the following command to set the desired Java version as the default:
`export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk-11.0.12.jdk/Contents/Home`

Note: Replace the path "/Library/Java/JavaVirtualMachines/jdk-11.0.12.jdk/Contents/Home" with the path of your desired Java version.

5. Verify the Changes: To verify that the default Java version has been changed successfully, run the `java -version` command again. It should now display the version you set as the default.

Pros Cons
1. Provides flexibility to switch between Java versions based on specific needs. 1. Command-line interface may be intimidating for novice users.
2. Works system-wide, ensuring the set Java version is used for all Java-based applications. 2. Requires knowledge of the correct path for each Java version.
3. Allows for granular control over the default Java version, even if multiple versions are installed. 3. Manually changing the default version may break compatibility with certain applications.

Method 2: Changing the Default Java Version via Java Preference Pane

If you prefer a graphical method for changing the default Java version on your Mac, you can use the Java Preference Pane. Follow these steps:

1. Open Java Preferences: Go to Applications > Utilities > Java Preferences.

2. Check Current Java Version: In the Java Preferences window, navigate to the "General" tab, and you will find the current default version of Java selected.

3. Choose a Different Version: To select a different version as the default, check the corresponding checkbox next to the desired version in the "Java Applications" section.

4. Apply the Changes: After selecting the desired Java version, close the Java Preferences window, and the changes will be applied immediately.

5. Verify the Changes: To verify that the default Java version has been changed successfully, open Terminal and run the `java -version` command. It should now display the version you set as the default.

Pros Cons
1. User-friendly graphical interface makes it easy to change the default Java version. 1. Limited options for managing multiple Java versions simultaneously.
2. Provides a visual representation of all installed Java versions on your Mac. 2. Compatibility may vary depending on the version of macOS and Java installed.
3. Covers both system-wide and per-user settings. 3. May not be available for newer versions of macOS or newer Java releases.

Method 3: Changing the Default Java Version via Third-Party Applications

There are several third-party applications available that can help you manage and switch between different Java versions on your Mac. One popular option is "jEnv." Follow these steps to change the default Java version using jEnv:

1. Install jEnv: Visit the jEnv GitHub page and follow the installation instructions for your operating system.

2. List Available Java Versions: In Terminal, use the following command to list all the Java versions installed on your Mac:
`jenv versions`

3. Add Java Version: To add a specific Java version to jEnv, use the following command:
`jenv add /Library/Java/JavaVirtualMachines/jdk-11.0.12.jdk/Contents/Home`

Note: Replace the path "/Library/Java/JavaVirtualMachines/jdk-11.0.12.jdk/Contents/Home" with the path of your desired Java version.

4. Set the Desired Java Version: Once you have added the Java version to jEnv, use the following command to set it as the default:
`jenv global 11.0.12`

Note: Replace "11.0.12" with the version number you want to set as the default.

5. Verify the Changes: To verify that the default Java version has been changed successfully, run the `java -version` command in Terminal. It should now display the version you set as the default.

Pros Cons
1. Provides a centralized and streamlined method for managing multiple Java versions. 1. Requires installation and setup of a third-party application.
2. Allows for easy switching of Java versions based on project requirements. 2. Compatibility may vary depending on the selected third-party application.
3. Provides the ability to isolate Java versions for specific projects or directories. 3. Learning curve and additional configuration may be required.

Method 4: Changing the Default Java Version via IDE Preferences

If you primarily work with integrated development environments (IDEs) such as Eclipse, IntelliJ IDEA, or NetBeans, you can change the default Java version within the IDE preferences. The exact method varies between IDEs, but the general steps are as follows:

1. Open the IDE: Launch your preferred IDE and open the preferences or settings menu. This is usually located under the "File" or "Preferences" tab.

2. Locate the Java Preferences: Within the IDE preferences, look for the section related to Java or JDK settings. It may be labeled as "Java," "Build," or "Compiler" settings.

3. Select the Desired Java Version: Within the Java preferences section, you will find options to select the desired JDK or Java version. Choose the version you want to set as the default.

4. Apply the Changes: After selecting the desired Java version, save the preferences, and the changes will be applied within the IDE.

5. Verify the Changes: To verify that the default Java version has been changed successfully, create a new Java project or open an existing one that uses the default configuration. The IDE should now use the version you set as the default.

Pros Cons
1. Easy to manage and switch between different Java versions within the IDE. 1. Limited to the IDE and its associated projects.
2. Provides a seamless development experience without system-wide changes. 2. Requires configuration within each IDE you use.
3. Allows for version-specific project configurations and targeted debugging. 3. May not be available in all IDEs or require specific plugin installations.

What to Do If You Can’t Change Default Java Version

If you encounter difficulties changing the default Java version on your Mac, here are a few possible fixes:

1. Make Sure Java Versions Are Installed: Check if the desired Java versions are installed on your Mac. If not, download and install them from the official Oracle website or other trusted sources.

2. Verify Path and Environment Variables: Ensure that the path to the desired Java version is correct and properly set as an environment variable. Double-check the commands and paths used in the methods mentioned above.

3. Restart Your Mac: Sometimes, a simple system restart can resolve Java-related issues. After restarting your Mac, try changing the default Java version again using any of the methods mentioned earlier.

4. Update macOS: Keeping your macOS up to date can help resolve compatibility issues with Java. Check for macOS updates and install any available updates that may address the problem.

Bonus Tips

Here are three bonus tips to further enhance your Java experience on Mac:

1. Use Homebrew: Consider installing Homebrew, a popular package manager for macOS. Homebrew provides an easy way to install and manage multiple versions of Java, as well as other developer tools.

2. Automate Java Version Switching: If you frequently switch between Java versions, you can automate the process by using shell scripts or aliases. This allows you to switch with a single command rather than manually entering the necessary steps each time.

3. Keep Multiple IDEs Installed: If you work with different Java projects that require specific versions of IDEs, it can be useful to keep multiple IDEs installed. Each IDE can be configured independently with its own default Java version settings.

5 FAQs

Q1: What happens if I delete a Java version that was set as the default?

A: If you delete a Java version that was set as the default, your system may revert to the next available Java version or, in some cases, the previously set default version. It’s recommended to change the default version to the desired one before deleting any installed Java versions.

Q2: Can I have multiple Java versions set as the default simultaneously?

A: No, you can only have one default Java version set at a time. Changing the default version will replace the previous setting with the newly selected version.

Q3: Are there any risks involved in changing the default Java version?

A: Changing the default Java version is generally a safe process. However, it’s important to ensure that the new version is compatible with the applications or projects you are working on. Incompatibilities could lead to errors or unexpected behavior.

Q4: Is it possible to revert to the original default Java version?

A: Yes, you can always revert to the original default Java version by following the same steps outlined in the methods above, but selecting the original version instead.

Q5: Will changing the default Java version affect other users on the same Mac?

A: The default Java version is applied system-wide, meaning it will affect all users on the same Mac. If other users require a different Java version, they will need to change the default on their individual accounts.

Final Thoughts

Changing the default Java version on your Mac can be essential for various reasons, including development requirements, compatibility, and performance enhancements. With the methods provided in this blog post, you can confidently switch between different Java versions to suit your specific needs. Whether you prefer command-line utilities, graphical interfaces, or IDE preferences, there is an option available for you. Keep in mind the potential risks and always ensure compatibility with your applications before making any changes.