Zing is available in Java SE levels 8.0, 7.0 and 6.0 which corresponds to the OpenJDK internal version scheme 1.8.0, 1.7.0 and 1.6.0.
If an application requires a specific update level within one of those three SE levels, like 8u111 (1.8.0_111), the reason for that might be a security fix or a bugfix specifically addressing a Java SE API method used by the application.
The Zing Release Notes contain information about security fixes which were adopted from OpenJDK into Zing to address a known CVE. Major bugfixes regarding Java SE API methods are also listed.
If you need more information about the corresponding Java SE update level of the Zing version you are using, please contact Azul Customer Support.
The version numbering scheme for Zing follows the numbering scheme used for Ubuntu Linux. For example Zing version 15.05.1.0 denotes with the first two numbers the major version, here 15.05, where 15 stands for the year 2015 and 05 for the month of May. The 3rd and 4th numbers are the minor version, 1.0 in this example.