Three simple steps to build an optimized OpenJDK 1.8 binary (tar file) for Power:

1. Install docker - i.e. sudo apt-get install docker.io
2. Execute below command from the command line:

git clone https://github.com/OpenPOWER-BigData/build-opt-openjdk.git; cd build-opt-openjdk

3. Execute below command from the command line:

sudo docker run --rm -v `pwd`:/ws bigtop/slaves:trunk-ubuntu-16.04-ppc64le bash -l -c "cd /ws; ./build_openjdk.sh https://github.com/mtbrandy/openjdk-jdk8u.git jdk8u152-b03-opt"