I'm back in Java after 5 years

I enrolled a free course at https://courses.edx.org with the title "Fundamentals of Java EE Development". It's really great I hope it will help me refresh my memory in Java.

first I followed the guide to install the necessary tools for this course.
https://prod-edxapp.edx-cdn.org/assets/courseware/v1/f9292ed1b6d208828257761a04df54e9/asset-v1:RedHat+JB083x+3T2018+type@asset+block/JB083x_SG_Updated.pdf

Install oracle java jdk 8 in ubuntu

sudo apt-get -y install software-properties-common

sudo add-apt-repository -y ppa:webupd8team/java 

sudo bash -c "echo deb http://http.debian.net/debian jessie-backports main >> /etc/apt/sources.list" 

sudo bash -c "echo deb http://ppa.launchpad.net/webupd8team/java/ubuntu trusty main >> /etc/apt/sources.list.d/webupd8team-java.list" 

sudo bash -c "echo deb-src http://ppa.launchpad.net/webupd8team/java/ubuntu trusty main >> /etc/apt/sources.list.d/webupd8team-java.list" 

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys EEA14886 

sudo apt-get update 

sudo apt-get -y upgrade 

echo debconf shared/accepted-oracle-license-v1-1 select true | sudo debconf-set-selections 

echo debconf shared/accepted-oracle-license-v1-1 seen true | sudo debconf-set-selections

sudo apt-get -y install oracle-java8-installer oracle-java8-set-default

https://stackoverflow.com/questions/48356434/install-java-8-jdk-1-8-using-vagrant-up-not-working-on-debian


update: 23/9/2018
this is more clearer
https://thishosting.rocks/install-java-ubuntu/

Running Tomcat and PostgresSQL in Docker

https://blog.lukaspradel.com/dockerizing-a-tomcat-postgresql-java-web-application/

https://tomcat.apache.org/tomcat-6.0-doc/appdev/sample/