set java_home permanently ubuntu

C++
#Update repo
sudo apt update

# Install java 8 from ubuntu repo
sudo apt install openjdk-8-jdk -y

#Set JAVA_HOME Path
ls /usr/lib/jvm/java-8-openjdk-amd64/
 export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64
 echo $JAVA_HOME
 
 #Add JAVA bin directory to the PATH variable
 export PATH=$PATH:$JAVA_HOME/bin
 echo $PATH
 java -versionsudo gedit /etc/profile
#add following lines

JAVA_HOME=/usr/lib/jvm/{your jdk path}
PATH=$PATH:$HOME/bin:$JAVA_HOME/bin
export JAVA_HOME
export JRE_HOME
export PATH
#logout to update the changes
Source

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