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javajava-8epochlocaldatejsonserializer

LocalDate to Epoch by Ignoring DayLightSaving

Business case:

A date wield of dataType LocalDate needs to be converted into epoch.

private LocalDate someDate;

Problem I am having is, with day light saving in place sometimes date is getting converted to n-1.

Example: Date is 28-Feb-2037 is converted into => 27-Feb-2037 which is incorrect.

Explanation: When we are converting from LocalDate to Epoch and taking the ZoneId as system default, it takes in consideration the daylight savings. For this reason the epoch is decreasing by 1 hour and when UI again converts it to date it becomes n-1 date 23:00:00 hrs.

My conversion code looks like this

someDate.atStartOfDay(ZoneId.systemDefault()).toEpochSecond() * 1000); //systemDefault = EUROPE/PARIS

How to ignore Daylight-Savings while conversion?

Solution

  • By Ignoring timezone below code will do the job for you

    localDate.atStartOfDay().atOffset(UTC).toEpochSecond()

    Or Maybe you need this:

        TimeZone timeZone = TimeZone.getTimeZone("GMT+1");// Paris timezone without daylight saving
    localDate.atStartOfDay(timeZone.toZoneId()).toEpochSecond();

    The idea is to use a fixed zone offset to get rid of daylight saving.