$ wget --no-cookies --header "Cookie: oraclelicense=accept-securebackup-cookie;" http://download.oracle.com/otn-pub/java/jdk/7u65-b17/jdk-7u65-linux-x64.tar.gz
$ sudo update-alternatives --get-selections | grep ^java
java manual /usr/lib/jvm/java-8-oracle/jre/bin/java
javac manual /usr/lib/jvm/java-8-oracle/bin/javac
javadoc manual /usr/lib/jvm/java-8-oracle/bin/javadoc
javafxpackager manual /usr/lib/jvm/java-8-oracle/bin/javafxpackager
javah manual /usr/lib/jvm/java-8-oracle/bin/javah
javap manual /usr/lib/jvm/java-8-oracle/bin/javap
javapackager manual /usr/lib/jvm/java-8-oracle/bin/javapackager
javaws manual /usr/lib/jvm/java-8-oracle/jre/bin/javaws
javaws.real auto /usr/lib/jvm/java-9-oracle/bin/javaws.real
$ sudo update-alternatives --install /usr/bin/java java /opt/java-jdk/jdk-10.0.1/bin/java 1
$ sudo update-alternatives --install /usr/bin/javac javac /opt/java-jdk/jdk-10.0.1/bin/javac 1
$ sudo update-alternatives --install /usr/bin/javaws javaws /opt/java-jdk/jdk-10.0.1/bin/javaws 1
sudo apt-add-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java8-installer
# java -version
java version "1.8.0_45"
Java(TM) SE Runtime Environment (build 1.8.0_45-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.45-b02, mixed mode)
sudo update-alternatives --set java /usr/lib/jvm/java-8-oracle/bin/java
sudo update-alternatives --set javac /usr/lib/jvm/java-8-oracle/bin/javac
sudo update-alternatives --set javah /usr/lib/jvm/java-8-oracle/bin/javah
sudo update-alternatives --set javah /usr/lib/jvm/java-8-oracle/bin/javap
sudo update-alternatives --set javap /usr/lib/jvm/java-8-oracle/bin/javap
sudo update-alternatives --set javapackager /usr/lib/jvm/java-8-oracle/bin/javapackager
sudo update-alternatives --set javadoc /usr/lib/jvm/java-8-oracle/bin/javadoc
ref https://www.if-not-true-then-false.com/2014/install-oracle-java-8-on-fedora-centos-rhel/