package pr2;

import java.util.ArrayList;

public class MyStringTokenizer {
   
   private ArrayList<String> tokens;
   
   public MyStringTokenizer(String s) {
      int pos;
      tokens = new ArrayList<String>();
      s = s.trim();
      while (s.length() != 0) {
         pos = s.indexOf(' ');
         if (pos == -1) {
            tokens.add(s);
            return;
         }
         tokens.add(s.substring(0,pos));
         s = s.substring(pos+1);
         s = s.trim();
      }
   }
   
   public int countTokens() {
      return tokens.size();
   }
   
   public boolean hasMoreTokens() {
      return tokens.size() > 0;
   }
   
   public String nextToken() {
      if (tokens.size() == 0)
         return null;
      return tokens.remove(0);
   }

}