[OPENEJB-1012] Multi-threaded Singleton Lazy Instantiation Issue

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.1
• Fix Version/s: 3.1.1
• Component/s: container system
• Assignee: David Blevins
• Reporter: David Blevins
• Created: 28/Mar/09 00:56
• Updated: 28/Mar/09 00:59
• Resolved: 28/Mar/09 00:59

Description

Old code foolishly used an "if (instance == null) instance = createInstance()" which is not thread safe – my bad .

Current code now uses Atomics and Futures to guarantee only one thread will win the right to lazily construct the singleton.