Getting “unixtime” in Java

问题

Date.getTime() returns milliseconds since Jan 1, 1970. Unixtime is seconds since Jan 1, 1970. I don't usually code in java, but I'm working on some bug fixes. I have:

Date now = new Date();      
Long longTime = new Long(now.getTime()/1000);
return longTime.intValue();

Is there a better way to get unixtime in java?

回答1:

Avoid the Date object creation w/ System.currentTimeMillis(). A divide by 1000 gets you to Unix epoch.

As mentioned in a comment, you typically want a primitive long (lower-case-l long) not a boxed object long (capital-L Long) for the unixTime variable's type.

long unixTime = System.currentTimeMillis() / 1000L;

回答2:

Java 8 added a new API for working with dates and times. With Java 8 you can use

import java.time.Instant
...
long unixTimestamp = Instant.now().getEpochSecond();

Instant.now() returns an Instant that represents the current system time. With getEpochSecond() you get the epoch seconds (unix time) from the Instant.

来源：https://stackoverflow.com/questions/732034/getting-unixtime-in-java