Does JIRA use a third-party library for User Preferences or is it In-House?

[crf · Accepted solution]

This depends on exactly what you mean, but the best answer is probably "a bit of both".  I'll try to give the complete picture of things as best as I can.

• The Shared Access Layer (SAL) utilities for cross-product development defines a UserSettingsService.  SAL is in-house.
• The JIRA implementation of the UserSettingsService is a thin wrapper around its UserPropertyManager, a JIRA-specific API.
• JIRA's UserPreferencesManager is also just a thin wrapper around UserPropertyManager. It's pretty worthless, except that it presents the properties as a Preferences object from the atlassian-core library. That was a noble but ultimately doomed effort to unify a common cross-product platform and predates SAL.  It's mostly useless today, but there are still a few things that need it, like the cron expression editor on the filter subscription page.
• The UserPropertyManager delegates to the  JiraPropertySetFactory using the entity name ApplicationUser and the entity ID of the app_user row that corresponds to the user.  This is also a JIRA-specific API.
• The JiraPropertySetFactory creates instances of an OpenSymphony PropertySet, a typed key-value store in an Open Source library that you can find on BitBucket.  The OpenSymphony libraries are best known as the original authors of Webwork (still in JIRA, but most other products have moved on to using Struts).  Although PropertySet is open source, I'm not aware of anybody else that uses it outside of Atlassian.
• The implementation for PropertySet is split across two main ones that JIRA uses (there are several others in existence which JIRA does not use, including those based on Hibernate, non-cluster-safe caching strategies, EJB, and more):
  • The original implementation is OFBizPropertySet, which you can find in the main PropertySet library.  As you can see in its implementation, it interacts directly with the GenericDelegator from Atlassian's OFBiz Entity Engine Fork. This is a very old fork of a small portion of the Apache OFBiz project.  Although OFBiz itself has many products that use it, JIRA is very likely the only consumer of our highly customized fork of its entity engine.  (The other Atlassian products use Hibernate for this.)
  • In most cases (including user preferences) the PropertySet implementation we use is one that I wrote, and it uses QueryDSL under the hood.  That implementation is closed source, but if you have access to JIRA's sources, you can find its implementation split across CachingOfBizPropertySet and CachingOfBizPropertyEntryStore.

[Chad Elstad]

Fantastic. Thank you for your wonderfully thorough answer. Good stuff!