Best way to list files in Java, sorted by Date Modified?

Question

I want to get a list of files in a directory, but I want to sort it such that the oldest files are first. My solution was to call File.listFiles and just resort the list based on File.lastModified, but I was wondering if there was a better way.

Edit: My current solution, as suggested, is to use an anonymous Comparator:

File[] files = directory.listFiles();

Arrays.sort(files, new Comparator<File>(){
    public int compare(File f1, File f2)
    {
        return Long.valueOf(f1.lastModified()).compareTo(f2.lastModified());
    } });

Answer 1

I think your solution is the only sensible way. The only way to get the list of files is to use File.listFiles() and the documentation states that this makes no guarantees about the order of the files returned. Therefore you need to write a Comparator that uses File.lastModified() and pass this, along with the array of files, to Arrays.sort().

Answer 2

You might also look at apache commons IO, it has a built in last modified comparator and many other nice utilities for working with files.