[MAPREDUCE-5530] Binary and source incompatibility in mapred.lib.CombineFileInputFormat between branch-1 and branch-2

• Type: Sub-task
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 2.1.1-beta
• Fix Version/s: 2.2.0
• Component/s: mrv1, mrv2
• Target Version/s: 2.2.0
• Assignee: Robert Kanter
• Reporter: Robert Kanter
• Created: 24/Sep/13 00:42
• Updated: 30/Jun/15 07:14
• Resolved: 02/Oct/13 16:11

Description

mapred.lib.CombineFileInputFormat in branch-1 has this method:

protected boolean isSplitable(FileSystem fs, Path file)

In branch-2, mapred.lib.CombineFileInputFormat is now a subclass of mapreduce.lib.input.CombineFileInputFormat, from which it inherits the similar method:

protected boolean isSplitable(JobContext context, Path file)

This means that any code that subclasses mapred.lib.CombineFileInputFormat and does not provide its own implementation of protected boolean isSplitable(FileSystem fs, Path file) will not be binary or source compatible if it tries to call isSplitable with a FileSystem argument anywhere (that is, if compiled against branch-1, it will throw a NoSuchMethodError if run against branch-2; also, it won't even compile against branch-2).