java生成指定范围的随机日期

public static String randomDateBetweenMinAndMax(){ 
    Calendar calendar = Calendar.getInstance(); 
    //注意月份要减去1 
    calendar.set(1990,11,31); 
    calendar.getTime().getTime(); 
    //根据需求，这里要将时分秒设置为0 
    calendar.set(Calendar.HOUR_OF_DAY, 0); 
    calendar.set(Calendar.MINUTE, 0); 
    calendar.set(Calendar.SECOND,0); 
    long min = calendar.getTime().getTime();; 
    calendar.set(2013,11,31); 
    calendar.set(Calendar.HOUR_OF_DAY,0); 
    calendar.set(Calendar.MINUTE,0); 
    calendar.set(Calendar.SECOND,0); 
    calendar.getTime().getTime(); 
    long max = calendar.getTime().getTime(); 
    //得到大于等于min小于max的double值 
    double randomDate = Math.random()*(max-min)+min; 
    //将double值舍入为整数，转化成long类型 
    calendar.setTimeInMillis(Math.round(randomDate)); 
    return calendar.getTime().toString(); 
  } 

System.out.println(new Date(2013,10,10)); 

public static void getDateBetweenMaxAndMin(){ 
    List<Date> list = new ArrayList<Date>(); 
    Calendar calendar = Calendar.getInstance(); 
    calendar.set(2010,10,10); 
    Date minDate = calendar.getTime(); //最小时间 
    calendar.set(2013,11,1); 
    Date maxDate = calendar.getTime();//最大时间 
    //计算两个时间点相隔多少天 
    int totalDays = Ints.checkedCast((maxDate.getTime() - minDate.getTime()) / (1000 * 60 * 60 * 24)); 
    calendar.setTime(minDate); 
    calendar.set(Calendar.HOUR_OF_DAY,0); 
    calendar.set(Calendar.MINUTE,0); 
    calendar.set(Calendar.SECOND,0); 
    for(int i = 0;i<=totalDays;i++){ 
      if(i!=0){ 
        //天数加1 
        calendar.add(Calendar.DAY_OF_MONTH,1); 
      } 
      list.add(calendar.getTime()); 
    } 
  }