Add an option to allow the JDK version to be selected

[ossarga]

As part of the use command add in an option to select the JDK to install on the node. We could do this by having pre-canned install scripts to install the different JDK versions. This would mean the valid values that can be supplied to the option are fixed.

In the above case, by default we install JDK 1.8 and copy its install script to the provisioning directory. If a different JDK version is specified, we would copy the appropriate install script to the provisioning directory.

[ossarga]

@rzvoncek has suggested we https://sdkman.io/ to switch JDK versions. We should definitely give this a try.

[ossarga]

@adejanovski has run tests that required the ability to switch Java clients using Jabba.

curl -sL https://github.com/shyiko/jabba/raw/master/install.sh | bash && . ~/.jabba/jabba.sh
jabba install [email protected]
jabba alias default [email protected]
sudo update-alternatives --install /usr/bin/java java ${JAVA_HOME%*/}/bin/java 20000
sudo update-alternatives --install /usr/bin/javac javac ${JAVA_HOME%*/}/bin/javac 20000