Here is an example of how to use the DirectoryFileComparator class from the org.apache.commons.io package in Java:

import java.io.File;
import org.apache.commons.io.comparator.DirectoryFileComparator;

public class Example {
    public static void main(String[] args) {
        File[] files = ...
        Arrays.sort(files, DirectoryFileComparator.DIRECTORY_COMPARATOR);
    }
}

In this example, we are sorting an array of File objects using the DirectoryFileComparator.DIRECTORY_COMPARATOR constant. This comparator sorts files in the following order:

• Directories come before files
• Directories and files are sorted by their name

The Arrays.sort() method is used to sort the files array using the DirectoryFileComparator.DIRECTORY_COMPARATOR constant as the comparator.

It's worth noting that the DirectoryFileComparator class is an extension of AbstractFileComparator class, that uses the File class's natural ordering to compares files. The DIRECTORY_COMPARATOR constant is an instance of this class, that is configured to work as described above.