[IO-142] Add facility to sort file lists/arrays to Comparator implementations

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.4
• Fix Version/s: 2.0
• Component/s: Utilities

Environment

Java SE 5 - Windows, Linux

• Assignee: Niall Pemberton
• Reporter: Al Scherer
• Created: 04/Dec/07 21:54
• Updated: 21/Jul/10 17:00
• Resolved: 29/Nov/08 04:49

Description

I searched your current Commons-IO issues/feature requests and did not find the following so I'd like to propose it as a feature request.

Given a filename filter and dir name, the method would return a List<File> of the files that match the filter in last-modified timestamp order.

Sun explicitly does not provide this functionality - from the Sun Java SE 5 API Javadocs, File's listFiles() method descriptions include the following disclaimer:
"There is no guarantee that the name strings in the resulting array will appear in any specific order; they are not, in particular, guaranteed to appear in alphabetical order."

I needed the files in last-modified order so I wrote code to do it and would be glad to share the code with the commons project if you feel it would be useful.

The signature is:

• public List<File> getFileListInTimestampOrder(FilenameFilter filter, String dirName)

I've already written, tested and used code to do this.

There are additional flavors that might be worthwhile, too.

• public List<File> getFileListInTimestampOrderReversed(FilenameFilter filter, String dirName)
• public List<File> getFileListInNameOrder(FilenameFilter filter, String dirName)
• public List<File> getFileListInNameOrderReversed(FilenameFilter filter, String dirName)

BTW, I originally posted this on commons-lang but was given feedback that it might be a better fit here.

Issue Links

• relates to: IO-145 File Comparator implementations