[HADOOP-10792] Add FileSystem#closeIfNotReferred method

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Won't Fix
• Component/s: fs
• Assignee: Unassigned
• Reporter: Kousuke Saruta
• Created: 07/Jul/14 19:21
• Updated: 18/May/17 12:32
• Resolved: 18/May/17 12:32

Description

FileSystem#close closes FileSystem even if the same instance of FileSystem is referred by someone.

For instance, a library using FileSystem calls FileSystem.get, and a program using the library calls FileSystem.get, both of instances of FileSystem is same.

When the library and the program is implemented as different threads and one calls FileSystem.close, another fails most of operations of FileSystem.

So, we need the method like cloesIfNotReferred, which closes FileSystem only if a instance of FileSystem is not referred by anyone.

Issue Links

• relates to: HADOOP-4655 FileSystem.CACHE should be ref-counted