Java .lastModified format

Hi everyone,

I am trying to implement a (date,time) check using the ".lastModified" field of a Java file object.

However, I am do not understand the format of the answer:

>> FileObj = java.io.File(getenv('WINDIR'));

>> FileObj.lastModified ans = 1.498033301774000e+12

Are these the milliseconds elapsed since 01.Jan.1970? If so the following code should provide today's date (04.Aug.2017):

>> secs = FileObj.lastModified/1000;

>> [today.y,today.m,today.d,today.h,today.mi,today.s] = datevec(datenum([1970 1 1 0 0 secs]));

>> today

today =

     y: 2017
     m: 6
     d: 21
     h: 8
    mi: 21
     s: 41.774000000001251

Any ideas? Thanks in advance.

Cheers

[DCagigas]

My bad...

If I check my "C:Windows" folder it was indeed modified on the 21.Jun.17, at 10:21:41. Which means 2 hours have to be added to the script:

[today.y,today.m,today.d,today.h,today.mi,today.s] = datevec(datenum([1970 1 1 2 0 Millisecs/1000]));

today =

     y: 2017
     m: 6
     d: 21
     h: 10
    mi: 21
     s: 41.774000000004889

Answer 1

[Sindhu Yerragunta]

Hi Dicagigas,

Please refer the following Java documentation

https://docs.oracle.com/javase/7/docs/api/java/io/File.html#lastModified()

The returned milliseconds from lastModified are measured since the epoch (00:00:00 GMT, January 1, 1970). So you need to add GMT difference of your country to the hour argument of 'datenum' function.

For example, for India the time is GMT+5.30, so you need to add an offset of 5 hours 30 minutes.

[today.y,today.m,today.d,today.h,today.mi,today.s] = datevec(datenum([1970 1 1 5 30 secs]));

Hope this answers your query.

-Sindhu

[DCagigas]

Thanks Sindhu for the quick reply.

May I ask you one further question? Are there any files/folders that will keep the "true" data/time even if the user modifies Windows date/time?

Cheers