Install dependencies

sudo apt update
sudo apt install openjdk-11-jdk maven -y

Build and Run

mvn clean install
java -jar target/ChatServer-1.0.0-jar-with-dependencies.jar s1 conf 

Run with Remote Debugging activated

java -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=*:8001 -jar target/ChatServer-1.0.0-jar-with-dependencies.jar s1 config