:~$ update-alternatives --config java
There are 2 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                            Priority   Status
------------------------------------------------------------
* 0            /usr/lib/jvm/java-11-openjdk-amd64/bin/java      1101      auto mode
  1            /usr/lib/jvm/java-11-openjdk-amd64/bin/java      1101      manual mode
  2            /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java   1081      manual mode

Press <enter> to keep the current choice[*], or type selection number:

netbeans_jdkhome="/usr/lib/jvm/java-8-openjdk-amd64/"