Create a random alphanumeric String in Java

StringsAndThings.java

public class StringsAndThings {

    private static final char[] characters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
    private static final Random random = new Random(new Date().getTime());

    public static void main(String[] args) {
        final String randomString = StringsAndThings.createRandomString(1000);
        System.out.println(randomString);
    }

    private static String createRandomString(int length) {
        final StringBuffer stringBuffer = new StringBuffer();
        for (int i = 0; i < length; i++) {
            String randomValue;
            if (random.nextInt(2) == 1) {
                randomValue = String.valueOf(random.nextInt(10));
            } else {
                randomValue = Character.toString(characters[random.nextInt(26)]);
            }
            stringBuffer.append(randomValue);
        }
        return stringBuffer.toString();
    }

}