[PHOENIX-5246] PhoenixAccessControllers.getAccessControllers() method is not correctly implementing the double-checked locking

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 4.14.0
• Fix Version/s: 4.15.0, 5.1.0, 4.14.2
• Labels: SFDC
• Assignee: Swaroopa Kadam
• Reporter: Thomas D'Silva
• Created: 17/Apr/19 22:12
• Updated: 22/Jul/19 23:32
• Resolved: 19/Apr/19 22:46

Description

By elserj on PHOENIX-5070:

This looks to me that the getAccessControllers() method is not correctly implementing the double-checked locking "approach" as per https://en.wikipedia.org/wiki/Double-checked_locking#Usage_in_Java (the accessControllers variable must be volatile).

If we want to avoid taking an explicit lock, what about using AtomicReference instead? Can we spin out another Jira issue to fix that?

Issue Links

• relates to: PHOENIX-5070 NPE when upgrading Phoenix 4.13.0 to Phoenix 4.14.1 with hbase-1.x branch in secure setup
• links to: GitHub Pull Request #487