How to make MATLAB read the environment variable JAVA_HOME

My question is how do I make MATLAB read the environment variable JAVA_HOME.

I enter the Matlab command

jenv

and get the following answer

ans =

JavaEnvironment with properties:

Version: "Java 1.8.0_202-b08 with Oracle Corporation Java HotSpot(TM) 64-Bit Server VM mixed mode"

Home: "/Applications/MATLAB_R2023a.app/sys/java/jre/maci64/jre"

Library: "/Applications/MATLAB_R2023a.app/sys/java/jre/maci64/jre/lib/server/libjvm.dylib"

Status: loaded

Configuration: "factory"

I enter the Matlab command

getenv JAVA_HOME

and get the following answer

ans = 0x0 empty char array

So I realize that for some reason JAVA_HOME has not been set properly. So I proceed to set the environement variable JAVA_HOME as instructed in:

https://www.mathworks.com/help/compiler_sdk/java/configure-your-java-environment.html

I am running MATLAB on a Mac computer running IOS version 15.2, so according to the instructions I enter the following in ~/.zprofile

export JAVA_HOME="/Applications/MATLAB_R2023a.app/sys/java/jre/maci64/jre"

PATH="$JAVA_HOME/bin:${PATH}"

I do a echo $JAVA_HOME and I see the correct value for JAVA_HOME

but after restarting Matlab and entring in the command window

getenv JAVA_HOME

I still get

ans = 0x0 empty char array

Can anyone let me know what I am doing wrong, that MATLAB does not get the environment variable JAVA_HOME?

[Walter Roberson]

The issue here is that when MATLAB is started from icon or dock, then it is not being invoked through an interactive shell. The approaches you have been using only set environment variables for interactive shells.

The documented method is to use launchctl setenv . However, settings done through this manner are lost upon reboot. I am having trouble finding information about setting persistent environment variables for OS-X Yosemite (10.10) and later. (Other than path -- for that use lauchctl config )

[dpb]

@Walter Roberson, as you are aware I "know nuthink!" about Mac OS X, but curiosity struck...I found an old <Stack Exchange thread> with a relatively late addition to it that indicates "...anyone on MacOS 10.15 (Catalina) and up ...you need to use a .zshenv file instead of .bash_profile. This is because by default since Catalina, the terminal uses zhs instead of bash."

I have no idea if any of the above is true or not, nor if it will help, but there it is...feel free to delete if is of no value.

However, seems awfully complex...

[dpb]

@Walter Roberson, as you are aware I "know nuthink!" about Mac OS X, but curiosity struck...I found an old <Stack Exchange thread> with a relatively late addition to it that indicates "...anyone on MacOS 10.15 (Catalina) and up ...you need to use a .zshenv file instead of .bash_profile. This is because by default since Catalina, the terminal uses zhs instead of bash."

I have no idea if any of the above is true or not, nor if it will help, but there it is...feel free to delete if is of no value/irrelevant.

However, seems awfully complex...

[Walter Roberson]

.zshenv and .bash_profile are both related to interactive shells, and are not used when starting applications from icon or dock.

[dpb]

So, you link the icon to a batch file that starts MATLAB from a shell, maybe?

What a mess...apparently at least one thing Bill's Boys did more simply.

Answer 1

[Image Analyst]

Maybe try using setenv to set it up in your startup.m file.

Answer 2

[Walter Roberson]

Potentially you could edit the .matlab7rc.sh file. See https://www.mathworks.com/help/matlab/ref/matlabmacos.html#bunueg9-5

[dpb]

That says .matlab7rc.sh is again only used if start from terminal so leaves one in the same place it appears that the usual from the icon in Applications folder won't show any effect?

I guess your spelunking hasn't uncovered any way for the user to set a persistent environment variable on MacOS, Walter?

Would it work if did the above hack of tying the icon to a batch file that starts MATLAB? I presume that is possible...

[Walter Roberson]

In MacOS, starting MATLAB from icon or dock is done by executing the shell script bin/matlab inside the MATLAB installation folder. So a shell script is executed -- just not an interactive shell script.

[dpb]

Ah so..then to fool Father Jobs would require starting terminal and then poking it with the MATLAB command...