Resolving the Undefined JAVA_HOME Variable in macOS
Introduction:
On recent versions of macOS, the Java runtime is no longer included by default. While it can be installed as an optional package, users may encounter an issue where the JAVA_HOME environment variable is not set correctly.
Problem:
Java applications rely on the JAVA_HOME variable to determine the location of the Java Development Kit (JDK). Without a proper setting, these applications may fail to run.
Solution:
To correct the JAVA_HOME variable, you can add the following lines to your ~/.bash_profile file:
export JAVA_HOME="(/usr/libexec/java_home -v 1.6)" export JAVA_HOME="(/usr/libexec/java_home -v 1.7)" export JAVA_HOME="(/usr/libexec/java_home -v 1.8)" export JAVA_HOME="(/usr/libexec/java_home)"
Note:
- The "-v" flag displays the full path to the JDK.
- If you installed OpenJDK through Homebrew, you'll need to run the following command:
sudo ln -sfn /usr/local/opt/openjdk/libexec/openjdk.jdk /Library/Java/JavaVirtualMachines/openjdk.jdk
Additional Information:
- The first three lines are specific to macOS High Sierra (10.13) and Mojave (10.14) with Oracle JDK.
- The fourth line is applicable to macOS Lion (10.7) to Sierra (10.12) with Apple Java or Oracle JDK.
- The JAVA_HOME variable should now be correctly set, allowing Java applications to run properly.
The above is the detailed content of Why is My JAVA_HOME Variable Undefined on macOS and How Do I Fix It?. For more information, please follow other related articles on the PHP Chinese website!

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