[LOG4J2-3618] Multiple PropertySources with identical priority cannot be added to PropertiesUtil Environment

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.17.2
• Fix Version/s: 2.24.0
• Component/s: Core
• Assignee: Unassigned
• Reporter: Phillip Webb
• Created: 13/Oct/22 02:10
• Updated: 16/Aug/24 11:59
• Resolved: 16/Aug/24 11:59

Description

The org.apache.logging.log4j.util.PropertiesUtil.Environment maintains a set of sources by using a ConcurrentSkipListSet backed with a PropertySource.Comparator.

Somewhat surprisingly, the ConcurrentSkipListSet will not add an item if comparing it to an existing one returns 0. This means that all PropertySource implementations must have unique getPriority() results. I think this might be better to use a Set that uses equals/hashCode to determine if items can be added and only use the Comparator for sorting.

Issue Links

• links to: PR #2454