anchor.diff:  RUN bash -c 'source ${SDKMAN_DIR}/bin/sdkman-init.sh && sdk install java ${JAVA_VERSION}'
   
   # Configure R Java home
  -RUN bash -c 'source ${SDKMAN_DIR}/bin/sdkman-init.sh && R CMD javareconf' 
  +RUN bash -c 'source ${SDKMAN_DIR}/bin/sdkman-init.sh && R CMD javareconf'
   
   # Cleanup
   RUN apt-get -y clean
  
positive.code: FROM ubuntu:focal
  
  ARG DEBIAN_FRONTEND noninteractive
  
  # Use specific Java version
  ARG JAVA_VERSION 11.0.11.hs-adpt
  
negative.code:     apt-utils \
      ca-certificates
  
  # Enforce https-only Ubuntu apt repositories
  # RUN sed -i 's|http://archive.ubuntu.com/ubuntu|https://mirrors.kernel.org/ubuntu|g' /etc/apt/sources.list
  
  # Install support for managing locales
  