Jira is a Java-based web application, so it needs to have a Java environment installed. This can be a Java Development Kit (JDK) or a Java Runtime Environment (JRE). The executable installer that comes with Windows or Linux contains the necessary files and will install and configure the JRE for you. However, if you want to use archive distributions, you will need to make sure that you have the required Java environment installed and configured.

Jira 8 requires Java 8 (also known as 1.8). If you run Jira on an unsupported Java version, including its patch version, you may run into unexpected errors. The following table shows the supported Java versions for JIRA:

With the recent licensing changes made to Oracle JDK by Oracle, efforts are currently underway to add support for OpenJDK. However, at the time of writing, OpenJDK is not officially supported.