Something

 public char pickTile()
   {
 Random ran = new Random(); 
 int n = this.tiles.length;
while (true) {
 int randomNumber = ran.nextInt(n);

if (randomNumber >= 1) { 
this.LETTER_COUNT[randomNumber] = (this.LETTER_COUNT[randomNumber] - 1);
this.tiles[randomNumber] = new TileType(Pool.ALPHABET[randomNumber], Pool.LETTER_COUNT[randomNumber]);

return this.ALPHABET[randomNumber];
}
}