Java used to be a favourite programming language for most of the developers. It was initially developed by sun microsystems. Oracle then took over Sun microsystems. Java used to be free until version 8 (Java 8). But Oracle has changed its license agreements recently. The following link provides clarity on the terms and condition to use Java. Following are free Java alternatives.
There are times when you need a specific version of Java to be installed instead of the latest version. The following post will brief on the steps required to remove Java 8 and install Java 7 in Ubuntu 16.04
Always use the latest version of Java as there are quite a lot of bug fixes and security vulnerability has been fixed.
Removing Java 8
Open Terminal and enter the following commands.
sudo update-alternatives –remove-all java
sudo update-alternatives –remove-all javac
sudo update-alternatives –remove-all javaws
sudo rm -rf /usr/lib/jvm/jdk1.8.0
Install Java 7
sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
Since Java 7 is no longer available in their repository, you need to manually download it from Oracle site.
Once the JDK 7 tar (jdk-7u80-linux-x64.tar.gz) is downloaded. Paste it in the below location
Now run the following command
sudo apt-get install oracle-java7-installer
After installation you also need to update alternatives by running the following command.
sudo update-alternatives –install “/usr/bin/java” “java” “/usr/lib/jvm/java-7-oracle/jdk1.7.0_80/bin/java” 1
sudo update-alternatives –install “/usr/bin/javac” “javac” “/usr/lib/jvm/java-7-oracle/jdk1.7.0_80/bin/javac” 1
sudo update-alternatives –install “/usr/bin/javaws” “javaws” “/usr/lib/jvm/java-7-oracle/jdk1.7.0_80/bin/javaws” 1
Once the above steps are completed. Check the java version from terminal
It should display jdk 1.7