An implementation of DateTimeFormat compatible in Client & Server for GWT

DateTimeFormat.java

public abstract class DateTimeFormat {
	static DateTimeFormat getFormat(String pattern)
    {
        if (GWT.isClient())
            return new DateTimeFormatClient(pattern);
        else
            return new DateTimeFormatServer(pattern);
    }
	
    public abstract String format(Date date);
    
    public abstract Date parse(String dateString);

    @GwtCompatible
    private static class DateTimeFormatClient extends DateTimeFormat
    {
    	protected String pattern;
    	
        public DateTimeFormatClient(String pattern)
        {
            this.pattern = pattern;
        }


        public String format(Date date)
        {
            return com.google.gwt.i18n.client.DateTimeFormat.getFormat(pattern).format(date);
        }
        
        public Date parse(String stringDate){
        	return com.google.gwt.i18n.client.DateTimeFormat.getFormat(pattern).parseStrict(stringDate);
        }
    }

    private static class DateTimeFormatServer extends DateTimeFormatClient
    {

        public DateTimeFormatServer(String pattern)
        {
            super(pattern);
        }


        @GwtIncompatible("Server format")
        public String format(Date date)
        {
            return (new java.text.SimpleDateFormat(pattern)).format(date);
        }  
        
        @GwtIncompatible("Server parse")
        public Date parse(String dateString){
        	try{
        		return (new java.text.SimpleDateFormat(pattern)).parse(dateString);
        	}catch(Exception ex){
        		throw new IllegalArgumentException("No se puede convertir a fecha: "+ dateString);
        	}
        }

    }
}