CircleCI 2 で Oracle Java 8を入れる

swagger-genを動かすためにJavaが必要だったので
CircleCI2にJava8を入れたときのメモ

# Javascript Node CircleCI 2.0 configuration file
#
# Check https://circleci.com/docs/2.0/language-javascript/ for more details
#
version: 2
jobs:
  build:
    docker:
      # specify the version you desire here
      - image: circleci/node:6.11.2

    working_directory: ~/repo

    steps:
      # install java 8
      - run: echo "oracle-java8-installer shared/accepted-oracle-license-v1-1 boolean true" > debconf.txt
      - run: sudo debconf-set-selections debconf.txt
      - run: sudo apt-get install software-properties-common
      - run: sudo add-apt-repository "deb http://ppa.launchpad.net/webupd8team/java/ubuntu xenial main"
      - run: sudo apt-get update
      - run: sudo apt-get install oracle-java8-installer