A complete guide to install Java/JRE/JDK on Ubuntu including Ubuntu 16.04 LTS Xenial Xerus.
Many programs needs Java Runtime Environments (JRE) to run properly. In Ubuntu, to install Java there are lots of options available – openjre, defaultjre or oraclejre. This article describes how to install those and configure JAVA_HOME environment variable.
Table of Contents
Install Default JRE/JDK
Unless your package requires specific Oracle Java, OpenJDK/JRE; you can go ahead with installing default JRE/JDK which would work in most of the cases.
- Run below command to update the package index
sudo apt-get update
- Check if Java is already installed in your system by running below command
java -version
If you don’t get a message with Java version, then Java is not installed in your system. You can proceed to install Java.
- To install default Java Runtime Environment (JRE), run below command from terminal
sudo apt-get install default-jre
- To install default Java Development Kit (JDK), run beow command from terminal
sudo apt-get install default-jdk
This is everything you need to have Java installed in your system. After installation you can run java -version to check whether Java is installed.
Installing OpenJDK 8
- To install OpenJDK 8 run below commands.
- for Java Runtime Environment
sudo apt-get install openjdk-8-jre
- for Java Development Kit
sudo apt-get install openjdk-8-jdk
To Install Oracle JDK 8 via PPA
WebUpd8 team maintains a PPA for all Oracle Java versions. Run below command to add the PPA.
sudo apt-get install python-software-properties sudo add-apt-repository ppa:webupd8team/java sudo apt-get update
Run below commands to install Oracle Java 8 in Ubuntu, Linux Mit and derivatives
sudo apt-get install oracle-java8-installer
Setting up JAVA_HOME environment variable
- Check the path where Java is installed. Run below command
sudo update-alternatives --config java
- This would give a list of Java paths if you have multiple version of Java is installed in your system. If only one version is installed, then you would get a response like this:
The Java is installed in path /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java.
- Open
/etc/environmentfile via administrator mode in your favorite text editor
sudo gedit /etc/environment
- Add below line in the file and save the file.
JAVA_HOME="/usr/lib/jvm/java-8-openjdk-amd64/jre"
Make sure to change the path according to your system.
- Run below command to reload the file
source /etc/environment
- Run below command to check if your Java installation setting of
JAVA_HOMEis correct.
echo $JAVA_HOME
Questions, suggestions? Drop a comment using comment box below.
