Starter setup for Clojure installation

rxjava-clojure-setup.sh

# installing Java JDK 1.8, Maven 3.3.9, Node 7.x, Clojure on ubuntu 16.04.2 lts (xenial xerus)
# script written for interactive reference only (no apt install -y flags..etc.)
# 2017 03 19

# Oracle 8 JDK (JDK 8u121) 
# visit Java SE downloads, accept license agreement
sudo mkdir -p -v /opt/java/64
tar xvzf jdk-8u121-linux-x64.tar.gz 
sudo mv -v jdk1.8.0_121 /opt/java/64 && rm jdk1.8.0_121.tar.gz
sudo update-alternatives --install /usr/bin/java java /opt/java/64/jdk1.8.0_121/bin/java 100
sudo update-alternatives --install /usr/bin/javac javac /opt/java/64/jdk1.8.0_121/bin/javac 100

# installing apache maven in /opt/maven
sudo mkdir -p -v /opt/maven
wget http://mirror.cc.columbia.edu/pub/software/apache//maven/maven-3/3.3.9/binaries/apache-maven-3.3.9-bin.tar.gz
tar xzvf apache-maven-3.3.9-bin.tar.gz
sudo mv -v apache-maven-3.3.9 /opt/maven && rm apache-maven-3.3.9-bin.targ.gz

# update (& export) maven env vars (see M2_HOME, M2, MAVEN_OPTS)
sudo echo "M2_HOME=/opt/maven/apache-maven-3.3.9" | sudo tee -a /etc/environment
sudo echo "PATH=$M2_HOME/bin:$PATH" | sudo tee -a /etc/profile

# installing leiningen
sudo mkdir -p -v /opt/bin/
wget -O lein https://raw.githubusercontent.com/technomancy/leiningen/stable/bin/lein
sudo mv -v lein /opt/bin/lein
sudo chmod a+x /opt/bin/lein
sudo echo "PATH=$PATH:/opt/bin/" | sudo tee -a /etc/profile
. /etc/profile
lein version

# verify java installation
sudo update-alternatives --display java
sudo update-alternatives --display javac
java -version
javac -version

# verify maven
mvn --version

# verify leiningen
lein repl