Get the UNIX timestamp from UUID version 1

java, unix-timestamp, uuid

Solution

From the docs for `timestamp()`:

The resulting timestamp is measured in 100-nanosecond units since midnight, October 15, 1582 UTC.

So you need to offset it from that. For example:

Calendar uuidEpoch = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
uuidEpoch.clear();
uuidEpoch.set(1582, 9, 15, 0, 0, 0); // 9 = October
long epochMillis = uuidEpoch.getTime().getTime();

long time = (uuid.timestamp() / 10000L) + epochMillis;
// Rest of code as before

Problem

In our Java application we are trying to get the UNIX time from the UUID version 1. But it's not giving the correct date time values. ``` long time = uuid.timestamp(); time = time / 10000L; // Dividing by 10^4 as it's in 100 nanoseconds precision Calendar c = Calendar.getInstance(); c.setTimeInMillis(time); c.getTime(); ``` Can someone please help?

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