java 获取一天零点零分零秒时间戳

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1.日期格式的

Calendar calendar = Calendar.getInstance();
        calendar.setTime(new Date());
        calendar.set(Calendar.HOUR_OF_DAY, 0);
        calendar.set(Calendar.MINUTE, 0);
        calendar.set(Calendar.SECOND, 0);
        long date =calendar.getTime().getTime();
        return String.valueOf(date);

格式转换

1.Calendar 转化 String

Calendar calendat = Calendar.getInstance();

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

String dateStr = sdf.format(calendar.getTime());

 

2.String 转化Calendar

String str="2012-5-27";

SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");

Date date =sdf.parse(str);

Calendar calendar = Calendar.getInstance();

calendar.setTime(date);

 

3.Date 转化String

SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");

String dateStr=sdf.format(new Date());

 

4.String 转化Date

String str="2012-5-27";

SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");

Date date= sdf.parse(str);

 

5.Date 转化Calendar

Calendar calendar = Calendar.getInstance();

calendar.setTime(new java.util.Date());

 

6.Calendar转化Date

Calendar calendar = Calendar.getInstance();

java.util.Date date =calendar.getTime();

 

7.String 转成 Timestamp

Timestamp ts = Timestamp.valueOf("2012-1-14 08:11:00");

 

8.Date 转 TimeStamp

SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

String time = df.format(new Date());

Timestamp ts = Timestamp.valueOf(time);

2.时间戳

long current = System.currentTimeMillis();
                long zero = current/(1000*3600*24)*(1000*3600*24) - TimeZone.getDefault().getRawOffset();

public static void main(String[] args) {
        long current=System.currentTimeMillis();//当前时间毫秒数
        long zero=current/(1000*3600*24)*(1000*3600*24)-TimeZone.getDefault().getRawOffset();//今天零点零分零秒的毫秒数
        long twelve=zero+24*60*60*1000-1;//今天23点59分59秒的毫秒数
        long yesterday=System.currentTimeMillis()-24*60*60*1000;//昨天的这一时间的毫秒数
        System.out.println(new Timestamp(current));//当前时间
        System.out.println(new Timestamp(yesterday));//昨天这一时间点
        System.out.println(new Timestamp(zero));//今天零点零分零秒
        System.out.println(new Timestamp(twelve));//今天23点59分59秒
}