Question

I want to convert the current date to integer value. By default, it returns long. When I try to convert long to integer, and afterwards I convert the integer value to date, means it shows 1970’s date,

 int i = (int) new Date().getTime();
 System.out.println("Integer : " + i);
 System.out.println("Long : "+ new Date().getTime());
 System.out.println("Long date : " + new Date(new Date().getTime()));
 System.out.println("Int Date : " + new Date(i));

the output as follows:

Integer : 1292838124
Long : 1345617601771
Long date : Wed Aug 22 12:10:01 IST 2012
Int Date : Fri Jan 16 04:37:18 IST 1970

Any one please help me out, how to convert current date to integer(10 digit number)?

Answer 1

The issue is that an Integer is not large enough to store a current date, you need to use a Long.

The date is stored internally as the number of milliseconds since 1/1/1970.

The maximum Integer value is 2147483648, whereas the number of milliseconds since 1970 is currently in the order of 1345618537869

Putting the maximum integer value into a date yields Monday 26th January 1970.

Edit: Code to display division by 1000 as per comment below:

    int i = (int) (new Date().getTime()/1000);
    System.out.println("Integer : " + i);
    System.out.println("Long : "+ new Date().getTime());
    System.out.println("Long date : " + new Date(new Date().getTime()));
    System.out.println("Int Date : " + new Date(((long)i)*1000L));

Integer : 1345619256
Long : 1345619256308
Long date : Wed Aug 22 16:37:36 CST 2012
Int Date : Wed Aug 22 16:37:36 CST 2012