How to Switch between Java Versions on Ubuntu Linux

If you have installed multiple JDK on ubuntu and sometimes you might need to change the version of installed JAVA to get few things working with one version and few other things working with another version of JAVA.

Lets first identify which all JDK are installed on your ubuntu, this can be done using “update-java-alternatives –list” command as,

$ update-java-alternatives --list
java-1.11.0-openjdk-amd64      1111       /usr/lib/jvm/java-1.11.0-openjdk-amd64
java-1.8.0-openjdk-amd64       1081       /usr/lib/jvm/java-1.8.0-openjdk-amd64

As we can see above, we have two JDK installed, java 1.11.0 and java 1.8.0 , now if we want to change the default Java, we can use below command . Note, you will need to enter the selection number as shown in the table to choose appropriate java

 $ sudo update-alternatives --config java
There are 2 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                            Priority   Status
------------------------------------------------------------
* 0            /usr/lib/jvm/java-11-openjdk-amd64/bin/java      1111      auto mode
  1            /usr/lib/jvm/java-11-openjdk-amd64/bin/java      1111      manual mode
  2            /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java   1081      manual mode

Press  to keep the current choice[*], or type selection number: 2
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java to provide /usr/bin/java (java) in manual mode

Now, we can verify the updated JAVA version as,

 $ /usr/bin/java -version
openjdk version "1.8.0_212"
OpenJDK Runtime Environment (build 1.8.0_212-8u212-b03-0ubuntu1.18.04.1-b03)
OpenJDK 64-Bit Server VM (build 25.212-b03, mixed mode)
Android Android Commands Android Java Applications Application Libraries Application Stack / User Interface Bash / Shell Scripts Commands and Packages Compilation Content Management System - CMS Core Kernel C Programs Development & Build Development Environment Setup Errors & Failures Flutter git Go Language Programs Hardware Platforms HTML JAVA Programs Kernel & Device Drivers Linux, OS Concepts and Networking Linux Device Drivers Linux Host, Ubuntu, SysAdmin Linux Kernel Linux Networking Middleware Libraries, HAL Monetization / Google AdSense Multimedia - Audio, Video, Images NDK / Middleware / HAL OS Concepts PHP Programming Languages RaspberryPi Scripting and Automation Search Engine Optimisation ( SEO ) Social Media Socurce Code Management ( SCM ) System Administration, Security Testing and Debugging Uncategorized User Interface Web design and development Wordpress Yocto / Bitbake / Openembedded

Leave a Reply / Ask Question