FileVisitor / Are we feature frozen yet?

Alan Bateman Alan.Bateman at
Tue Aug 6 14:15:04 UTC 2013

On 06/08/2013 06:39, Ben Evans wrote:
> Hi,
> I have a suggestion for a point lambdafication change which I don't think
> anyone's proposed yet. (As usual, if my Google-fu has failed me, please
> point me at the relevant discussion).
> In java.nio.file we have the FileVisitor interface, which defines 4 methods.
> We also have the SimpleFileVisitor class which defines sane (basically
> no-op) implementations of all the methods.
> In using FileVisitor, I've noticed that visitFile() tends to be overridden
> / used far more often than the others. It would be nifty if it we could
> lambdify in such a way that a lambda expression could be fed to
> Files.walkFileTree().
> Could we add default implementations to FileVisitor (those from
> SimpleFileVisitor seem reasonable) for all methods except visitFile() ?
> This would then make code like this possible:
> Path homeDir = Paths.get("/Users/kittylyst");
> Files.walkFileTree(homeDir, (p, attrs) ->  {
> System.out.println(p.getFileName()); return FileVisitResult.CONTINUE; });
> I have a patch which demonstrates this - let me know if there's potential
> here, and if anyone would be interested in sponsoring the patch.
Have you looked at the walk and find methods? (They currently return a 
CloseableStream but there is discussion on just returning a Stream).


More information about the core-libs-dev mailing list