Unix时代到Java Date对象。

I have a string containing the UNIX Epoch time, and I need to convert it to a Java Date object.

我有一个包含UNIX纪元时间的字符串，我需要将它转换为Java日期对象。

String date = "1081157732";
DateFormat df = new SimpleDateFormat(""); // This line
try {
  Date expiry = df.parse(date);
 } catch (ParseException ex) {
  ex.getStackTrace();
}

The marked line is where I'm having trouble. I can't work out what the argument to SimpleDateFormat() should be, or even if I should be using SimpleDateFormat().

这条有记号的线就是我遇到麻烦的地方。我无法计算SimpleDateFormat()的参数应该是什么，即使我应该使用SimpleDateFormat()。

7 个解决方案

#1

How about just:

只是如何:

Date expiry = new Date(Long.parseLong(date));

EDIT: as per rde6173's answer and taking a closer look at the input specified in the question , "1081157732" appears to be a seconds-based epoch value so you'd want to multiply the long from parseLong() by 1000 to convert to milliseconds, which is what Java's Date constructor uses, so:

编辑:根据rde6173的答案，仔细查看问题中指定的输入，“1081157732”似乎是一个基于秒的历元值，所以您需要将从parseLong()到1000的长乘以1000，将其转换为毫秒，这是Java的日期构造函数所使用的，因此:

Date expiry = new Date(Long.parseLong(date) * 1000);

#2

Epoch is the number of seconds since Jan 1, 1970..

纪元是自1970年1月1日以来的秒数。

So:

所以:

String epochString = "1081157732";
long epoch = Long.parseLong( epochString );
Date expiry = new Date( epoch * 1000 );

For more information: http://www.epochconverter.com/

更多信息:http://www.epochconverter.com/

#3

java.time

Using the java.time framework built into Java 8 and later.

使用java。在Java 8和之后构建的时间框架。

import java.time.LocalDateTime;
import java.time.Instant;
import java.time.ZoneId;

long epoch = Long.parseLong("1081157732");
Instant instant = Instant.ofEpochSecond(epoch);
ZonedDateTime.ofInstant(instant, ZoneOffset.UTC); # ZonedDateTime = 2004-04-05T09:35:32Z[UTC]

In this case you should better use ZonedDateTime to mark it as date in UTC time zone because Epoch is defined in UTC in Unix time used by Java.

在这种情况下，最好使用ZonedDateTime来标记UTC时区中的日期，因为在Java使用的Unix时间中，Epoch是用UTC定义的。

ZoneOffset contains a handy constant for the UTC time zone, as seen in last line above. Its superclass, ZoneId can be used to adjust into other time zones.

ZoneOffset包含一个方便的UTC时区常数，如上面最后一行所示。它的超类，ZoneId可以用来调整到其他时区。

ZoneId zoneId = ZoneId.of( "America/Montreal" );

#4

long timestamp = Long.parseLong(date)
Date expiry = new Date(timestamp * 1000)

#5

Better yet, use JodaTime. Much easier to parse strings and into strings. Is thread safe as well. Worth the time it will take you to implement it.

更好的是,使用JodaTime。更容易解析字符串和字符串。线程安全吗?值得你花时间去实现它。

#6

To convert seconds time stamp to millisecond time stamp. You could use the TimeUnit API and neat like this.

将秒时间戳转换为毫秒时间戳。您可以使用TimeUnit API，像这样简洁。

long milliSecondTimeStamp = MILLISECONDS.convert(secondsTimeStamp, SECONDS)

长milliSecondTimeStamp =毫秒。转换(secondsTimeStamp秒)

#7

Hum.... if I am not mistaken, the UNIX Epoch time is actually the same thing as

哼....如果我没弄错的话，UNIX纪元时间实际上是一样的

System.currentTimeMillis()

So writing

所以写

try {
    Date expiry = new Date(Long.parseLong(date));
}
catch(NumberFormatException e) {
    // ...
}

should work (and be much faster that date parsing)

应该可以工作(并且要比日期解析快得多)