public int read(CharBuffer cb) {
   if (count-- == 0) return -1; // Indicates end of input
   cb.append(capitals[rand.nextInt(capitals.length)]);
   for (int i = 0; i < 4; i++) {
     cb.append(vowels[rand.nextInt(vowels.length)]);
     cb.append(lowers[rand.nextInt(lowers.length)]);
   }
   cb.append(" ");
   return 10; // Number of characters appended
 }