Format a datetime string to time only
I'm retrieving a datetime from a SQLite DB which comes out in the format...
2011-01-24 02:45:00
In C# I can simply use DateTime.Parse("2011-01-24 02:45:00").ToString("HH:mm")
in order to get the string 02:45
Is their a way I can I do this in Android/Java? My code in my Android app loo开发者_如何学Goks like this...
// dateStr below is logging as correctly being yyyy-MM-dd HH:mm:ss format
String dateStr = cursor.getString(cursor.getColumnIndex("start_time"));
SimpleDateFormat sdf = new SimpleDateFormat("HH:mm");
String shortTimeStr = sdf.format(dateStr); // <-- throws IllegalArgumentException
EDIT: Thanks to both doc_180 and Konstantin Burov - the examples given have helped me sort out the problem. Part of the issue was that I was importing java.sql.Date instead of java.util.Date. I've changed things around and it's working perfectly for me now.
You need to do the following.
try {
Date date = null;
date = df.parse("2011-01-24 02:45:00");
SimpleDateFormat sdf = new SimpleDateFormat("HH:mm");
String shortTimeStr = sdf.format(date);
System.out.println(shortTimeStr);
} catch (ParseException e) {
// To change body of catch statement use File | Settings | File Templates.
e.printStackTrace();
}
As I mentioned in comment, you should store the time as milliseconds instead of string. Otherwise, I do not see any other way than creating a middleman object Date.
SimpleDateFormat.format expects Date or Calendar as argument while you're passing a String. Convert the String into Date first.
String dateStr = cursor.getString(cursor.getColumnIndex("start_time"));
SimpleDateFormat toFullDate = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date fullDate = toFullDate.parse(dateStr);
SimpleDateFormat sdf = new SimpleDateFormat("HH:mm");
String shortTimeStr = sdf.format(fullDate);
And yeah, I'd rather stored date as long in the database, so getting a Date object then would be more trivial:
Long dateMilliseconds = cursor.getLong(cursor.getColumnIndex("start_time"));
Date fullDate = new Date(dateMilliseconds);
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