import java.io.File;
import java.io.IOException;
public class FileUtil {
public static void main(String[] a)throws IOException{
showDir(1, new File("d:\\Java_Dev"));
}
static void showDir(int indent, File file) throws IOException {
for (int i = 0; i < indent; i++)
System.out.print('-');
System.out.println(file.getName());
if (file.isDirectory()) {
File[] files = file.listFiles();
for (int i = 0; i < files.length; i++)
showDir(indent + 4, files[i]);
}
}
}