Based on the error message you are seeing, it seems that there might be a problem with the Java installation or configuration. Here are a few things you can try to resolve the issue:
Check if the Java version you are using is compatible with Pentaho Data Integration (Kettle) 9.1. According to the Pentaho documentation, Java 8 is still the supported Java version for Kettle 9.1, so it seems like you have the correct Java version installed.
Make sure that the Java path is set correctly. You can do this by running the command echo $JAVA_HOME in the terminal. If the command returns a blank line, it means that the Java path is not set. In that case, you can set the Java path by adding the following line to the .bash_profile file in your home directory:
After adding this line, save the .bash_profile file and restart the terminal.
Check if there are any conflicting Java installations on your system. To do this, run the command java -version in the terminal. If the output shows a different Java version than the one you have installed, it means that there might be a conflicting Java installation on your system. In that case, you can try uninstalling the conflicting Java version or changing the Java path to point to the correct Java installation.
Try running Kettle as an administrator. Sometimes, Kettle might require administrator privileges to access certain files or settings. To do this, right-click on the Kettle icon and select "Run as administrator". HEB Partner