If you're using bash, all you have to do is:
echo export "JAVA_HOME=\$(/usr/libexec/java_home)" >> ~/.bash_profile
If you're using zsh (which probably means you're running macOS Catalina or newer), then it should instead be:
echo export "JAVA_HOME=\$(/usr/libexec/java_home)" >> ~/.zshrc
In either case, restart your shell.
If you have multiple JDK versions installed and you want it to be a specific one, you can use the -v flag to java_home like so:
echo export "JAVA_HOME=\$(/usr/libexec/java_home -v 1.7)" >> ~/.bash_profile
If you're using bash, all you have to do is:
echo export "JAVA_HOME=\$(/usr/libexec/java_home)" >> ~/.bash_profile
If you're using zsh (which probably means you're running macOS Catalina or newer), then it should instead be:
echo export "JAVA_HOME=\$(/usr/libexec/java_home)" >> ~/.zshrc
In either case, restart your shell.
If you have multiple JDK versions installed and you want it to be a specific one, you can use the -v flag to java_home like so:
echo export "JAVA_HOME=\$(/usr/libexec/java_home -v 1.7)" >> ~/.bash_profile
I just spent 2 hours setting this variable. The other answers did not work properly for me. I'm using macOS Catalina 10.15.4.
First, find your actual Java SDK Home directory:
/usr/libexec/java_home
Manually navigate there to make sure you don't have any mistakes due to incorrect versions, etc. For me, this was:
/Library/Java/JavaVirtualMachines/jdk-13.0.2.jdk/Contents/Home
Next, edit your terminal's profile. If you're using zsh, this will be:
vim ~/.zshrc
If you're not using zsh, this will be:
vim ~/.bash_profile
Inside, add the following new line anywhere in the file:
export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk-13.0.2.jdk/Contents/Home
Restart your terminal app (or source ~/.bash_profile), and it should work properly.
Videos
You can use /usr/libexec/java_home -v <version you want> to get the path you need for JAVA_HOME. For instance, to get the path to the 1.7 JDK you can run /usr/libexec/java_home -v 1.7 and it will return the path to the JDK. In your .profile or .bash_profile just add
export JAVA_HOME=`/usr/libexec/java_home -v <version>`
and you should be good. Alternatively, try and convince the maintainers of java tools you use to make use of this method to get the version they need.
To open '.bash_profile' type the following in terminal :
nano ~/.bash_profile
and add the following line to the file:
export JAVA_HOME=`/usr/libexec/java_home -v <version>`
Press CTRL+X to exit the bash. Press 'Y' to save changes.
To check whether the path has been added, type following in terminal:
source ~/.bash_profile
echo $JAVA_HOME
I was facing the same issue in MAC Catalina, If I edit .bash_profile i found export JAVA_HOME="/Library/Java/JavaVirtualMachines/jdk1.8.0_201.jdk/Contents/Home But When I run terminal echo $JAVA_HOME it was returning empty, Later I found that the file .zshrc was missing I created this file with
touch .zshrc
Then edit it by nano .zshrc and wrote
source ~/.bash_profile
Which solves my issue permanently