java获取前几个月或者后几个月的时间

//返回Date类型
    public static Date getTimeToDate(int month) {
        Date date = new Date();
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        calendar.add(Calendar.MONTH, month);
        date = calendar.getTime();
        return date;
    }


    public static void main(String[] args) {
        System.out.println(getTime(-3));//前三月
    }

//返回字符串类型
    public static String getTimeToString(int month) {
        Date date = new Date();
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        calendar.add(Calendar.MONTH, month);
        date = calendar.getTime();
        String defaultStartDate = new SimpleDateFormat("yyyyMMdd").format(date);
        return defaultStartDate;
    }

    public static void main(String[] args) {
        System.out.println(getTime(-3));//前三月
    }