字符串转时间类型
String data= "2018-12-12";
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd");
Date parse = simpleDateFormat.parse(data);这里有个小坑 MM一定要大写
判断两个时间相差天数
String data= "2018-12-12";
String data2= "2018-12-14";
Date parse = simpleDateFormat.parse(data);
Date parse2 = simpleDateFormat.parse(data2);
System.out.println((parse2.getTime()-parse.getTime())/(1000*3600*24));
获取指定时间的下一天
String data= "2018-12-12";
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-mm-dd");
Date parse = simpleDateFormat.parse(data);
Calendar calendar = new GregorianCalendar();
calendar.setTime(parse);
calendar.add(calendar.DATE,1);
Date time = calendar.getTime();
String format = simpleDateFormat.format(time);
System.out.println(format);