RecursionTest02.java

import java.util.*;

public class RecursionTest02
{
     public static void main(String [] args)
     {
          System.out.println(permutate("Dog"));
     }
     
     public static ArrayList<String> permutate(String n)
     {
          ArrayList<String> result = new ArrayList<String>();
          
          if(n.length() == 0) { result.add(""); return result; }
          if(n.length() == 1) { result.add(n);  return result; }
          
               for (int i = 0; i < n.length(); i++)
               {
                  String shorterWord = n.substring(0, i)
                        + n.substring(i + 1);
                  
                  ArrayList<String> shorterResult = new ArrayList<String>();
                  shorterResult = permutate(shorterWord);
                  
                  for(String e : shorterResult)
                  {
                       result.add(e);
                  }
               }
               
               return result;    
     }
}