Java Timestamp with Fractional Seconds

Question

How can I print Java Instant as a timestamp with fractional seconds like 1558766955.037 ? The precision needed is to 1/1000, as the example shows.

I tried (double) timestamp.getEpochSecond() + (double) timestamp.getNano() / 1000_000_000, but when I convert it to string and print it, it shows 1.558766955037E9.

It sounds like this is a *display* issue as much as anything else - if you write `double value = 1558766955.037;` and print that, I suspect you'll get the same result. So at that point, the problem isn't around timestamps - it's number formatting. I expect you'll find some other Stack Overflow questions around that. — Jon Skeet, May 25 '19 at 07:01

score 1 · Accepted Answer · answered May 25 '19 at 07:07

The result you're seeing is the secientific (e-) notation of the result you wanted to get. In other words, you have the right result, you just need to properly format it when you print it:

Instant timestamp = Instant.now();
double d = (double) timestamp.getEpochSecond() + (double) timestamp.getNano() / 1000_000_000;
System.out.printf("%.2f", d);

score 1 · Answer 2 · answered May 25 '19 at 07:12

As others pointed out it is formatting issue. For your specific format you could use Formatter with Locale that supports dot delimetted fractions :

Instant now = Instant.now();

double val = (double) now.getEpochSecond() + (double) now.getNano() / 1000_000_000;

String value = new Formatter(Locale.US)
                .format("%.3f", val)
                .toString();

System.out.print(value);

Prints :

1558768149.514

Slawomir Chodnicki · Answer 3 · 2019-05-25T07:05:44.203

0

System.out.printf("%.3f", instant.toEpochMilli() / 1000.0) should work.

edited May 25 '19 at 07:05

answered May 25 '19 at 07:01

Slawomir Chodnicki

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Java Timestamp with Fractional Seconds

3 Answers3