Running java with JAVA_OPTS env variable has no effect

Question

In a shell script, I have set the JAVA_OPTS environment variable (to enable remote debugging and increase memory), and then I execute the jar file as follows:

export JAVA_OPTS="-Xdebug -Xrunjdwp:transport=dt_socket,address=8001,server=y,suspend=n -Xms512m -Xmx512m"
java -jar analyse.jar $*

But it seems there is no effect of the JAVA_OPTS env variable as I cannot connect to remote-debugging and I see no change in memory for the JVM.

What could be the problem?

PS: I cannot use those settings in the java -jar analyse.jar $* command because I process command line arguments in the application.

Milord

Answer 1

I don't know of any JVM that actually checks the JAVA_OPTS environment variable. Usually this is used in scripts which launch the JVM and they usually just add it to the java command-line.

The key thing to understand here is that arguments to java that come before the -jar analyse.jar bit will only affect the JVM and won't be passed along to your program. So, modifying the java line in your script to:

java $JAVA_OPTS -jar analyse.jar $*

Should "just work".

Earwitness

See HEX's answer. That is how you set the options using an environment variable on OS X. – Casa

Answer 2

You can setup _JAVA_OPTIONS instead of JAVA_OPTS. This should work without $_JAVA_OPTIONS.

Litha

This this the real answer. I went looking around for hours to find this. – Casa

@Nerrve Special for you installed Windows XP. Works fine. Are you sure you did everything correctly? – Litha

@Nerrve You must create environment variable called _JAVA_OPTIONS. Example: cs417020.userapi.com/v417020976/3764/hwBZ419TXcQ.jpg – Litha

oops! you're right. its works! i had made a spelling mistake earlier :P thanks a bunch! – Jiva

You may also would use JAVA_TOOL_OPTIONS (#28328120) – Preposterous

@Preposterous your suggestion appears to be the correct answer. you should add it – Gobbet

I can't. I got "Trivial answer converted to comment" – Preposterous

Holy moly this worked. Why is this so badly documented? – Gunar

Beware: this prints a line to stderr – Headwork

Thanks, I was able to set _JAVA_OPTIONS environment variable using Java 8u282 running in a Docker container and it was picked up! – Placement

Answer 3

In the past 12 years some changes were made:

• Environment variable JDK_JAVA_OPTIONS: this is the recommended way to do what you wanted starting with Java 9, see Using the JDK_JAVA_OPTIONS Launcher Environment Variable in the Oracle Java 9 documentation, and this comprehensive answer What is the difference between JDK_JAVA_OPTIONS and JAVA_TOOL_OPTIONS when using Java 11?.

• Environment variable JAVA_OPTS: it was NOT and is NOT a standardized option. Some shell script wrappers for Java based tools do evaluate it, an example of how this works is in the answer from ZoogieZork.

• Environment variable _JAVA_OPTIONS (mentioned by HEX): it is nowadays deprecated/undocumented, see Oracle announcement (section "Add a new launcher environment variable JDK_JAVA_OPTIONS").

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