FileInputFormat directory traversal

[Ian Soboroff]

Is there a reason FileInputFormat only traverses the first level of  
directories in its InputPaths?  (i.e., given an InputPath of 'foo', it  
will get foo/* but not foo/bar/*).

I wrote a full depth-first traversal in my custom InputFormat which I  
can offer as a patch.  But to do it I had to duplicate the PathFilter  
classes in FileInputFormat which are marked private, so a mainline  
patch would also touch FileInputFormat.

Ian