Here is an example of how to use the DeletingPathVisitor class from the Apache Commons IO library to delete a directory and all of its contents:

import java.io.IOException;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.filefilter.TrueFileFilter;

public class DeleteDirectoryExample {
    public static void main(String[] args) {
        try {
            // Define the directory to be deleted
            String directory = "/path/to/directory";

            // Create a DeletingPathVisitor instance
            DeletingPathVisitor visitor = new DeletingPathVisitor();

            // Walk the directory tree and delete all files and directories
            FileUtils.walkFileTree(new File(directory), visitor, TrueFileFilter.INSTANCE, TrueFileFilter.INSTANCE);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

This will delete the directory and all of its contents. Be careful when using this code, as it can delete a lot of data quickly and permanently.