GWT: use DateTimeFormat on client and SimpleDateFormat on server

Question

I have a function that must work the same way on both client and server and it formats dates.

if (GWT.isClient())
{
  // Use DateTimeFormat
} else {
  // Use         


        

Answer 1

You can use com.google.gwt.i18n.shared.DateTimeFormat on both server and client:

Call the protected constructor to avoid GWT.create

String pattern = "yyyyMMdd"; /*your pattern here*/ 
DefaultDateTimeFormatInfo info = new DefaultDateTimeFormatInfo();
DateTimeFormat dtf = new DateTimeFormat(pattern, info) {};  // <= trick here

Example

Date d = dtf.parse("20120301");
CalendarUtil.addDaysToDate(d, -1);
String s = dtf.format(d);
// s now contains "20120229"

The trick is done by extending the DateTimeFormat so we can use protected constructor with DateTimeFormatInfo where we use the new DefaultDateTimeFormatInfo() to avoid calling of GWT.create