Today we are going to learn that how to install Java on Ubuntu 20.04. Before going to the Java installation let’s have a short introduction about it. Java is the most popular and interesting language used for programming, gaming and developing different tools. Most developers prefer Java to build Java based applications. Just follow the below steps for an easy installation.
Step 1: Update Your System
As it is a good practice to update your system before going to install any new package so update the system.
sudo apt update
Step 2: Install Java OpenJDK JDK on Ubuntu 20.04
To install the Java OpenJDK on your Ubuntu 20.04 system type the below command in your terminal.
For Java 11 run the following command. And press Y when prompted.
sudo apt install openjdk-11-jdk
Output:
You’ll see the similar output upon successful installation.
Processing triggers for gnome-menus (3.36.0-1ubuntu1) …
Processing triggers for man-db (2.9.1-1) …
Processing triggers for ca-certificates (20190110ubuntu1) …
Updating certificates in /etc/ssl/certs…
0 added, 0 removed; done.
Running hooks in /etc/ca-certificates/update.d…
done.
done.
Processing triggers for sgml-base (1.29.1) …
Setting up x11proto-dev (2019.2-1ubuntu1) …
Setting up libxau-dev:amd64 (1:1.0.9-0ubuntu1) …
Setting up libice-dev:amd64 (2:1.0.10-0ubuntu1) …
Setting up libsm-dev:amd64 (2:1.2.3-1) …
Setting up libxdmcp-dev:amd64 (1:1.1.3-0ubuntu1) …
Setting up x11proto-core-dev (2019.2-1ubuntu1) …
Setting up libxcb1-dev:amd64 (1.14-2) …
Setting up libx11-dev:amd64 (2:1.6.9-2ubuntu1) …
Setting up libxt-dev:amd64 (1:1.1.5-1) …
For Java 8 run the given command.
sudo apt install -y openjdk-8-jdk
Output:
Upon successful installation you’ll see the similar output.
provide /usr/bin/idlj (idlj) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/wsimpo
rt to provide /usr/bin/wsimport (wsimport) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/jsadeb
ugd to provide /usr/bin/jsadebugd (jsadebugd) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/native
2ascii to provide /usr/bin/native2ascii (native2ascii) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/javah
to provide /usr/bin/javah (javah) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/clhsdb
to provide /usr/bin/clhsdb (clhsdb) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/extche
ck to provide /usr/bin/extcheck (extcheck) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/hsdb t
o provide /usr/bin/hsdb (hsdb) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/schema
gen to provide /usr/bin/schemagen (schemagen) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/xjc to
provide /usr/bin/xjc (xjc) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/jhat t
o provide /usr/bin/jhat (jhat) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/wsgen
to provide /usr/bin/wsgen (wsgen) in auto mode
Setting up openjdk-8-jdk:amd64 (8u252-b09-1ubuntu1) …
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/bin/applet
viewer to provide /usr/bin/appletviewer (appletviewer) in auto mode
Processing triggers for mime-support (3.64ubuntu1) …
Processing triggers for hicolor-icon-theme (0.17-2) …
Processing triggers for gnome-menus (3.36.0-1ubuntu1) …
Processing triggers for libc-bin (2.31-0ubuntu9) …
Processing triggers for desktop-file-utils (0.24-1ubuntu2) …
Step 3: Install Java OpenJDK JDK Headless
To install JDK headless simply fire the below command in your terminal.
For Java Headless 11 JDK.
sudo apt install -y openjdk-11-jdk-headless
For Java Headless 8 JDK.
sudo apt install -y openjdk-8-jdk-headless
Step 4: Install Java OpenJDK JRE on Ubuntu 20.04
Hit the command given below in your terminal.
For Java JRE 11.
sudo apt install -y openjdk-11-jre
Java JRE 8.
sudo apt install -y openjdk-8-jre
For Java JRE headless
You can install Java JRE headless with the help of following command.
For Java 11.
sudo apt install -y openjdk-11-jre-headless
For Java 8.
sudo apt install -y openjdk-8-jre-headless
Step 5: How To Set Default Java Version on Ubuntu 20.04
Run the below command to set the default java version on Ubuntu 20.04.
sudo update-alternatives --config java
Select the number from the list you want to make default java version.
Verify the installed Java version by running the below command.
java -version
Output:
sabi@Ubuntu:~$ java -version
openjdk version "1.8.0_252"
OpenJDK Runtime Environment (build 1.8.0_252-8u252-b09-1ubuntu1-b09)
OpenJDK 64-Bit Server VM (build 25.252-b09, mixed mode)
Step 6: Setting Up Environment Variables
For setting up environment variables you’ve to create a new file. To do this run the following command.
sudo nano /etc/profile.d/java.sh
And then provides the variables paths where the Java is installed.
export PATH=$PATH:/usr/lib/jvm/java-11-openjdk-amd64/bin/
export JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64/
export J2SDKDIR=/usr/lib/jvm/java-11-openjdk-amd64/
And finally source the file.
source /etc/profile.d/java.sh
That’s it you’ve successfully installed Java.
