Java中的日期格式转换

Question

我在项目中要求 将24小时格式转换为12小时格式 ，例如如果它是17:12:01它应该转换为05:12:01

Answer 1

Use two SimpleDateFormat objects - one to parse and the other to format the time.

Note also that 05:12:01 is not technically a 12 hour time (rather it appears to be an AM 24 hour time, given the lead 0 on the hour and the lack of a meridian designation). You probably want 5:12:01 PM .

It is possible that a 12 hour SimpleDateFormat will correctly parse a 24 hour time, provided that it is configured for lenient parsing. Just saying, so perhaps you need only one SimpleDateFormat.

Answer 2

You can use a SimpleDateFormat http://download.oracle.com/javase/6/docs/api/java/text/SimpleDateFormat.html to format it.

Date date = new Date(yourdate);
// format however you see fit
SimpleDateFormat format = new SimpleDateFormat("hh:mm:ss");
String formatted = format.format(date);

As suggested by Software Monkey, also use a SimpleDateFormat to parse your 24hr date if you don't already have it in millis.