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javadatesimpledateformatepoch

Simple date format giving wrong time

I have a time in milliseconds: 1618274313.

When I convert it to time using this website: https://www.epochconverter.com/, I am getting 6:08:33 AM.

But when I use SimpleDateFormat, I am getting something different:

SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss", Locale.getDefault());
System.out.println(sdf.format(new Date(1618274313)));

I am getting output as 23:01:14.

What is the issue in my code?

Solution

  • In your example, you are using time 1618274313 and you are assuming that it is in milliseconds. However, when I entered the same time on https://www.epochconverter.com/, I got below results:

    Please notice the site mentions: Assuming that this timestamp is in seconds.

    Now if we use that number multiplied by 1000 (1618274313000) as the input so that the site considers it in milliseconds, we get below results:

    Please notice the site now mentions: Assuming that this timestamp is in milliseconds.

    Now, when you will use 1618274313000 (correct time in milliseconds) in Java with SimpleDateFormat, you should get your expected result (instead of 23:01:14):

    SimpleDateFormat sdf=new SimpleDateFormat("HH:mm:ss", Locale.getDefault());
System.out.println(sdf.format(new Date(1618274313000)));