Uninstall Netbeans 11.2 -> error "Java SE Development Kit (JDK) was not found on this computer"

Hello,

I have installed Netbeans 11.2 first. After a while I expected that should update version 11.2 to version 12. But due that I not good understand how this works in Linux unfortunately Netbeans v12 is installed on a different place next to version 11.2
(On this moment I do not realize what I did wrong. Maybe is was in another directory and run the install script of 12 there instead of /u01/app/netbeans-11.2.)

But now I want to uninstall Netbeans-11.2 with the uninstall script: /u01/app/netbeans-11.2/uninstall.sh.

If I run this script I get this:
Quote:

Configuring the installer... Searching for JVM on the system... Java SE Development Kit (JDK) was not found on this computer JDK 8 is required for installing the NetBeans IDE. Make sure that the JDK is properly installed and run installer again. You can specify valid JDK location using --javahome installer argument. To download the JDK, visit http://www.oracle.com/technetwork/java/javase/downloads

Question: How do I find were the JDK is installed?

I have installed openjdk:
Quote:

sudo -c "yum install java-1.8.0-openjdk-devel"

in the dir /u01/app[/QUOTE]

With the command "rpm -qa | grep java" is this the result:
Quote:

java-1.8.0-openjdk-headless-1.8.0.265.b01-1.fc31.x86_64 tzdata-java-2020d-1.fc31.noarch java-1.8.0-openjdk-devel-1.8.0.265.b01-1.fc31.x86_64 javapackages-filesystem-5.3.0-6.fc31.noarch java-1.8.0-openjdk-1.8.0.265.b01-1.fc31.x86_64

So Java is installed, I think!

If I "java -version"
Quote:

openjdk version "1.8.0_265" OpenJDK Runtime Environment (build 1.8.0_265-b01) OpenJDK 64-Bit Server VM (build 25.265-b01, mixed mode)

If I do "which java":
Quote:

/usr/bin/java

I have this add to my ~/.bashrc:
Quote:

export JAVA_HOME=$(dirname $(dirname $(readlink $(readlink $(which java))))) export PATH=$PATH:$JAVA_HOME/bin export CLASSPATH=.:$JAVA_HOME/jre/lib:$JAVA_HOME/lib:$JAVA_HOME/lib/tools.jar

With "alternatives --config java", I get this:
Quote:

*+ 1 java-1.8.0-openjdk.x86_64 (/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.265.b01-1.fc31.x86_64/jre/bin/java)

And with echo $JAVA_HOME:
Quote:

/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.265.b01-1.fc31.x86_64/jre

And this is what I found in the netbeans.conf for version 11.2
Quote:

netbeans_jdkhome="/usr"

Probably wrong, But were else can jdkhome assign to?

Maybe a lot of information, but I hope that someone can give me the clue how this works in Linux, so that I better understand Linux.