如何以秒为单位获取当前UTC时间

Question

我有一个应用程序,需要以秒为单位比较时间.

我想知道如何以秒为单位获取当前的UTC时间.

有人可以发布一个例子,我们如何在Java中做到这一点？

Answer 1

你可以使用它来获得你想要时间的时区传递时区

Calendar cal = Calendar.getInstance(TimeZone.getTimeZone("UTC")); 

然后你可以在日历对象上调用你想要的任何东西

System.out.println(cal.get(Calendar.YEAR));
System.out.println(cal.get(Calendar.HOUR));
System.out.println(cal.get(Calendar.HOUR_OF_DAY));
System.out.println(cal.get(Calendar.MINUTE));

下面的示例以秒为单位比较两个日历

Calendar cal1 = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
Calendar cal2 = Calendar.getInstance(TimeZone.getTimeZone("UTC"));

// Set the dates for calendars
cal1.set(2011, 1, 1);
cal2.set(2011, 2, 2);

// Get the represented date in milliseconds as a long
long milis1 = cal1.getTimeInMillis();
long milis2 = cal2.getTimeInMillis();

// Calculate difference in milliseconds
long diff = milis2 - milis1;

// Calculate difference in seconds
long diffSecs = diff / 1000;

System.out.println("In seconds: " + diffSecs + " seconds");

Answer 2

System.currentTimeMillis的()