I was asked recently if I could run through the install guide for uniCenta oPOS (an open source point Point Of Sale application) to get a quick demo up and running. Below is a dump of the commands used to do so.

• Ubuntu 18.04
• Java 8u312
• MySQL 5.7.37
• uniCenta Opos 4.6.1

# Install the curl dependency so we're able to download packages via terminal
sudo apt-get install curl

# Download the unicentaopos installer community edition from SourceForge
curl -L  https://sourceforge.net/projects/unicentaopos/files/releases/linux/unicentaopos-4.6.1-linux-x64-installer.run/download > ./Downloads/unicentaopos-4.6.1-linux-x64-installer.run

# Install the Java 8 dependency
sudo apt install openjdk-8-jre

# Confirm the installation version
java -version

openjdk version "1.8.0_312"
OpenJDK Runtime Environment (build 1.8.0_312-8u312-b07-0ubuntu1~20.04-b07)
OpenJDK 64-Bit Server VM (build 25.312-b07, mixed mode)

# Find out where JRE is installed
ls -l `which java`
/etc/alternatives/java -> /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java

# Add the JAVA_HOME environment variable with the location of the JRE install
sudo echo 'JAVA_HOME="/usr/lib/jvm/java-8-openjdk-amd64/"' >> /etc/environment

# Mark the uniCenta installer as exectuable
chmod 755 ./Downloads/unicentaopos-4.6.1-linux-x64-installer.run

# Execute the uniCenta installer
sudo ./Downloads/unicentaopos-4.6.1-linux-x64-installer.run

# Mark all the resulting uniCenta installed scripts as executable
sudo chmod 755 /opt/unicentaopos-4.6.1/*.sh

# Fix the DOS line endings in uniCenta scripts to make them UNIX compatible
sudo apt-get install dos2unix
sudo dos2unix /opt/unicentaopos-4.6.1/start.sh

# Test the uniCenta application prior to configuring a database to make sure it runs
/opt/unicentaopos-4.6.1/start.sh

# Install MySQL Server 5.7
sudo apt update
sudo apt install mysql-server

# Configure a database to connect to (mysql 5.7)
sudo mysql

create database unicentaopos;
grant all on unicentaopos.* to 'unicentaopos'@'%' identified by 'pass';

# Start the uniCenta application and configure the database
/opt/unicentaopos-4.6.1/start.sh

After populating the Database fields, you may encounter:

"SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification."

In this case and for the purposes of a demo, set the DB options to:

"?zeroDateTimeBehavior=convertToNull&useSSL=false"

Save the configuration and fully close the application before opening and testing the configuration again.