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

// This program prints out the structure of a given directory or file
public class DirectoryCrawler {
   public static void main(String[] args) {
      Scanner console = new Scanner(System.in);
      System.out.print("directory or file name? ");
      String name = console.nextLine();
      File f = new File(name);
      if (!f.exists()) {
         System.out.println("That file or directory does not exist");
      } else {
         print(f);
      }
   }
   
   // pre: f.exists()
   // post: prints the name of the file
   // if the file is a directory, prints a complete listing of all
   // the files under this directory 
   public static void print(File f) {
      print(f, 0);
   }
   
   // pre: f.exists()
   // post: prints the name of the file with the given level of indentation
   // if the file is a directory, prints a complete listing of all
   // the files under this directory with more indentation
   private static void print(File f, int numIndents) {
      for (int i = 0; i < numIndents; i++) {
         System.out.print("    ");
      }
      System.out.println(f.getName());
      if (f.isDirectory()) {
         // print out everything under this directorys
         File[] subFiles = f.listFiles();
         for (int i = 0; i < subFiles.length; i++) {
            File subFile = subFiles[i];
            print(subFile, numIndents + 1);
         }
      }
   }
  
}