Installing Open JDK 8 on Debian or Ubuntu Systems

Configure your operating system to use the latest build of a Technology Compatibility Kit (TCK) Certified OpenJDK version 8, such as OpenJDK 8 (1.8.0_151 minimum). Java 9 and later are not supported.

Note: After installing the JDK, you may need to set JAVA_HOME to your profile:

• For shell or bash: export JAVA_HOME=path_to_java_home
• For csh (C shell): setenv JAVA_HOME=path_to_java_home

These instructions show you how to install OpenJDK. DataStax has tested OpenJDK at scale.

1. Check which version of the JDK your system is using:

   java -version

   If the OpenJDK is used, the results should look like:

   openjdk version "1.8.0_242"
   OpenJDK Runtime Environment (build 1.8.0_242-b09)
   OpenJDK 64-Bit Server VM (build 25.242-b09, mixed mode)

   If Oracle Java is used, the results should look like:

   java version "1.8.0_241"
   Java(TM) SE Runtime Environment (build 1.8.0_241-b07)
   Java HotSpot(TM) 64-Bit Server VM (build 25.241-b07, mixed mode)

2. Update the repositories:

   sudo apt-get update

3. Install OpenJDK:

   sudo apt-get install openjdk-8-jdk

   The latest JDK is installed.

4. Verify the version of the JDK:

   java -version

   openjdk version "1.8.0_242"
   OpenJDK Runtime Environment (build 1.8.0_242-b09)
   OpenJDK 64-Bit Server VM (build 25.242-b09, mixed mode)

5. If the correct version of Java is not being used, use the alternatives command to switch it:

   sudo update-alternatives --set java /usr/lib/jvm/jdk1.8.0_version/bin/java

6. Verify the version of the JDK:

   java -version

   openjdk version "1.8.0_242"
   OpenJDK Runtime Environment (build 1.8.0_242-b09)
   OpenJDK 64-Bit Server VM (build 25.242-b09, mixed mode)