Question

I need to get the day, month, year details from a Date value but getYear() is deprecated, gives year on 2 digits, and has problems with Y2K (2008 gives 108). The java doc recommends using java.util.calendar but it is not supported in GWT.

I want to avoid sending all the info back and forth between the server and client just to deal with dates.

Edit: Calendar might be supported Date handling functions should be implemented in GWT futur versions : http://code.google.com/p/google-web-toolkit/issues/detail?id=603

Answer 1

Do not use those deprecated methods on Date class in GWT.

If you don’t want to use third party Date implementations for GWT, You use a combination of DateTimeFormat along with string manipulation as a workaround for the time being, until GWT comes up with some better support for manipulating dates.

For date - 
DateTimeFormat.getFormat( "d-M-yyyy" ).format( new Date() ).split( "-")[0]

For month - 
DateTimeFormat.getFormat( "d-M-yyyy" ).format( new Date() ).split( "-")[1]

For year - 
DateTimeFormat.getFormat( "d-M-yyyy" ).format( new Date() ).split( "-")[2]

Edit-
Similarly, avoid using new Date( yy, mm, dd ) has come inconsistencies depending on the browser and date range.

I have use a simple DateUtil Class to create and parse Date objects in GWT, maybe of some use to you –

(Warning: Very crude, and work in progress)

public class DateUtil
{
    private static final String D_M_YYYY = "d-M-yyyy";
    private static final String DATE_SEPARATOR = "-";

    public static Date getDate( Integer dd, Integer mm, Integer yyyy )
    {
        if ( dd == null || mm == null || yyyy == null )
            return null;

        Date retVal = null;
        try
        {
            retVal = DateTimeFormat.getFormat( D_M_YYYY ).parse( dd + DATE_SEPARATOR + mm + DATE_SEPARATOR + yyyy );
        }
        catch ( Exception e )
        {
            retVal = null;
        }

        return retVal;
    }

    public static String getDayAsString( Date date )
    {
        return ( date == null ) ? null : DateTimeFormat.getFormat( D_M_YYYY ).format( date ).split( DATE_SEPARATOR )[0];
    }

    public static String getMonthAsString( Date date )
    {
        return ( date == null ) ? null : DateTimeFormat.getFormat( D_M_YYYY ).format( date ).split( DATE_SEPARATOR )[1];
    }

    public static String getYearAsString( Date date )
    {
        return ( date == null ) ? null : DateTimeFormat.getFormat( D_M_YYYY ).format( date ).split( DATE_SEPARATOR )[2];
    }

    public static boolean isValidDate( Integer dd, Integer mm, Integer yyyy )
    {
        boolean isvalidDate = true;

        try
        {
            String transformedInput = DateTimeFormat.getFormat( D_M_YYYY ).format( getDate( dd, mm, yyyy ) );
            String originalInput = dd + DATE_SEPARATOR + mm + DATE_SEPARATOR + yyyy;

            isvalidDate = transformedInput.equals( originalInput );
        }
        catch ( Exception e )
        {
            isvalidDate = false;
        }

        return isvalidDate;
    }
}