Groovy 怎么获取到前一天

def today = getNowDate()
//-1days
def yesterday = ?

给你copy的 apache组织的代码

    public static Date add(Date date, int calendarField, int amount) {
        if (date == null) {
            throw new IllegalArgumentException("The date must not be null");
        }
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.add(Calendar.DAY_OF_MONTH, amount);
        return c.getTime();
    }

如何调用

def yesterday = addDays(new Date(),-1)

http://simon-c.iteye.com/blog/945536