JAVA date处理

    Date now=new Date();Long nowTime=now.getTime();Long monthAgo=nowTime-1000*60*60*24*30L;//不加L不行...还得基本功好啊Calendar cal=Calendar.getInstance();cal.setTimeInMillis(monthAgo);SimpleDateFormat smf=new SimpleDateFormat("yyyy-MM-dd");end=smf.format(now);start=smf.format(cal.getTime());