You need the Process ID (PID) of your Java app to use it. Use jps (another JDK tool) to find it quickly: jps -l Use code with caution. Copied to clipboard
The JStack output will show you the thread stacks of your Java application, which can be useful for diagnosing and troubleshooting issues. install jstack on ubuntu
Verify that the JDK is installed correctly: You need the Process ID (PID) of your Java app to use it
ps aux | grep java # or jps -l