Java read all files in a directory

/**
 * @author lautturi.com 
 * Java example: java reading all files in folder 
 */

import java.io.File;
import java.util.*;

public class Lautturi {
	static void readFolder(File folder){
		for ( File fileEntry : folder.listFiles()) {
	        if (fileEntry.isDirectory()) {
	        	readFolder(fileEntry);
	        } else {
	            System.out.println(fileEntry.getName());
	        }
	    }
	}
	public static void main(String args[]) {

		File folder = new File("F:\\testdir");
		
		readFolder( folder);
	}
}