static String randomTime() {
        String hours = random(0,23);
        if (hours.length() == 1) {
            hours = "0" + hours;
        }
        String minutes = random(0,59);
        if (minutes.length() == 1) {
            minutes = "0" + minutes;
        }
        String seconds = random(0,59);
        if (seconds.length() == 1) {
            seconds = "0" + seconds;
        }
        return hours+":"+minutes+":"+seconds;
    }