计算自己活了多少天 SimpleDateFormat Date getTime()

```
package day0811;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Scanner;
/**
* 计算自己活了多少天
*
*/
public class SimpleDateFormatDemo {

public static void main(String[] args) throws ParseException {
// String birthday = "1981-11-13";
Scanner sc = new Scanner(System.in);
String birthday = sc.nextLine();
sc.close();
//规定好日期格式
String dateRegex = "\\d{4}-\\d{2}-[0-9]{2}";
if(!birthday.matches(dateRegex)){
System.out.println("日期格式不对");
}
String dateFormat = "yyyy-MM-dd";
SimpleDateFormat sdf = new SimpleDateFormat(dateFormat);
//利用SimpleDateFormat将String转为Date
Date birthdate = sdf.parse(birthday);
System.out.println(birthdate);

Date now = new Date();
//取得long毫秒数（1970年元旦0时到现在的毫秒数）
long birthlong = birthdate.getTime();
long nowlong = now.getTime();

long agelong = nowlong - birthlong;

long days = agelong/(24*60*60*1000);
System.out.println("恭喜您，已经活了"+days+"天");
}

}