How to set Java home (JAVA_HOME) on MAC OS

Following instruction can quickly help to set JAVA_HOME on mac machine :

• Open Terminal
• Type which java it will prompt /usr/bin/java in case JAVA is already installed but if it is not then you have to download from oracle.com.
• Let say JAVA is installed then Type java -version It will prompt below: 

         java version "11.0.3" 2019-04-16 LTS
         Java(TM) SE Runtime Environment 18.9 (build 11.0.3+12-LTS)
         Java HotSpot(TM) 64-Bit Server VM 18.9 (build 11.0.3+12-LTS, mixed mode

• For MAC java home path is /Library/Java/Home or if you have more than one version then it can be /Library/Java/JavaVirtualMachines/jdk-11.0.3.jdk/Contents/Home. In my system java home path was as above since my system has multiple jvm.
• To set JAVA HOME or Correct version of JAVA HOME run following :

           export JAVA_HOME=/Library/Java/Home

           or 

           export JAVA_HOME= /Library/Java/JavaVirtualMachines/jdk-11.0.3.jdk/Contents/Home

• Run echo $JAVA_HOME to check path has been set correctly.

        

        Note that this sets JAVA_HOME only for this session. If need to persist then we need to add this into ~/.profile. Following steps can help : 

• Open up Terminal (Applications >> Utilities >> Terminal)
• Type: emacs .profile
• add this to the end of the .profile file:

        JAVA_HOME=/Library/Java/Home
        or
        JAVA_HOME= /Library/Java/JavaVirtualMachines/jdk-11.0.3.jdk/Contents/Home

• export JAVA_HOME;
• Save and exit emacs (ctrl-x, ctrl-s; ctrl-x, ctrl-c)
• Open a new Terminal window and type: java -version.

       java version "11.0.3" 2019-04-16 LTS
       Java(TM) SE Runtime Environment 18.9 (build 11.0.3+12-LTS)
       Java HotSpot(TM) 64-Bit Server VM 18.9 (build 11.0.3+12-LTS, mixed mode

       Now we are all set with JAVA HOME.

Cheers,

Kapil