Review Bash Script

I need to review a bash script to download, install and initialized:
- Java-11-openjdk (LTS)
- Maven repository (ver. 3.8.6)
- Setup through the script Java Env and Maven (mvn package command)
- Selection of external packages (put in the script declaration as SOURCE VARIABLES)
- CAS v6.5.0-RC5 installation and initialization through the script (DB + Parameters of configuration)
- Default constant values in the initialization bash script, now the parameters are inserted manually.

Operating System: Centos 7
Access: VPN L2TP
Test: on your own environment on VM (no online server)
Deployment: on the staging server after all the procedure is fully functional