Java Random Alpha Numeric string generation

Generate a random alpha numeric string whose length is the number of characters specified. Characters will be chosen from the set of alpha-numeric characters. Count is the length of random string to create.

private static final String ALPHA_NUMERIC_STRING = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; 
public static String randomAlphaNumeric(int count) { 
 StringBuilder builder = new StringBuilder(); 
 while (count-- != 0) { 
  int character = (int)(Math.random()*ALPHA_NUMERIC_STRING.length()); 
  builder.append(ALPHA_NUMERIC_STRING.charAt(character)); 
 } 
 return builder.toString(); 
}