You can install a prebuilt OpenJDK Binary distribution with the following commands:
mkdir ~/jdk15
mkdir ~/Downloads
wget -O ~/Downloads/jdk15.tgz "https://github.com/AdoptOpenJDK/openjdk15-binaries/releases/download/jdk-15.0.2%2B7/OpenJDK15U-jdk_x64_linux_hotspot_15.0.2_7.tar.gz"
gzip -dc ~/Downloads/jdk15.tgz | tar --strip-components=1 -xvf - -C ~/jdk15
cat << EOF >> ~/.profile
#JDK
export JDK_HOME=${HOME}/jdk15
export JAVA_HOME=\${JDK_HOME}
export PATH=\${PATH}:\${JDK_HOME}/bin
EOF
Just copy and past them into your Terminal, reboot and you’re fine:
