/usr/lib/jvm/java-11-openjdk-amd64/bin seems to be no JDK!

[Mangonels]

I have java jdk & jre installed on Ubuntu 20.04, and I added: JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64 to jvmtop.sh (line 10), as I saw in a tutorial. Im asuming this counts as having a valid JDK environment path, but even if it doesn't, I already tried everything I mention here: https://askubuntu.com/questions/1248311/running-jvmtop-profile-the-java-home-environment-variable

However I get this message: /usr/lib/jvm/java-11-openjdk-amd64/bin seems to be no JDK! oddly enough, the path in the error seems to include bin, even though I only specified it up to java-11-openjdk-amd64.

I did nothing more and nothing less than what I mentioned. Am I missing something?

[Mangonels]

Got it to work by switching from java 11, to java 8. But how do you exit the profiling mode? Edit: well, I guess just disconnecing from ubuntu is one way.

[tangsaidi]

I can reproduce this problem using a Ubuntu machine with only Java 11 installed.

[tangsaidi]

This is likely because tools.jar was removed in JDK 9. Not sure if there's a fix to this problem.

[rgb1380]

I get the same problem with openjdk 17: /Users/user01/Library/Java/JavaVirtualMachines/openjdk-17.0.2/Contents/Home seems to be no JDK!

There is no solution for this?

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If I run any Java app with a newer version and run jvmtop on Java 8 I get this result:

These are IntelliJ and some Gradle processes running on Java11:

388753 inCompileDaemon [ERROR: Could not attach to VM] 
388828 inCompileDaemon [ERROR: Could not attach to VM] 
389039 inCompileDaemon [ERROR: Could not attach to VM] 
386926 ap.GradleDaemon [ERROR: Could not attach to VM] 
383163 ellij.idea.Main [ERROR: Could not attach to VM]

On Java 8 they look fine but IntelliJ probably runs on their own JDK:

391975 m.jvmtop.JvmTop   76m 7015m   22m   n/a  0.12%  0.00% O8U33   _   25   
390917 ap.GradleDaemon  597m 1820m  239m   n/a  0.06%  0.00% O8U33   _   37   
391314 inCompileDaemon  227m 1820m  135m   n/a  0.06%  0.00% O8U33   _   16   
391376 inCompileDaemon  174m 1820m  145m   n/a  0.00%  0.00% O8U33   _   15   
391256 inCompileDaemon  231m 1820m  154m   n/a  0.00%  0.00% O8U33   _   17   
392478 ellij.idea.Main [ERROR: Could not attach to VM]