(Quick Reference)
                formatDate
Purpose
Formats 
java.util.Date instances using the patterns defined by the 
SimpleDateFormat class.
Examples
<g:formatDate format="yyyy-MM-dd" date="${date}"/><g:formatDate date="${date}" type="datetime" style="MEDIUM"/><g:formatDate date="${date}" type="datetime" style="LONG" timeStyle="SHORT"/><g:formatDate date="${date}" type="time" style="SHORT"/>Description
Attributes
- date(required) - The date object to format
- format(optional) - The formatting pattern to use for the date, see SimpleDateFormat
- formatName(optional) - Look up- formatfrom the default MessageSource / ResourceBundle (i18n/*.properties file) with this key. If- formatand- formatNameare empty,- formatis looked up with '- default.date.format' key. Defaults to 'yyyy-MM-dd HH:mm:ss z' if the key not specified
- type(optional) - The type of format to use for the date / time.- formator- formatNamearen't used when- typeis specified. Possible values: 'date' - shows only date part, 'time' - shows only time part, 'both'/'datetime' - shows date and time
- timeZone(optional) - Sets the time zone for formatting. See TimeZone class.
- locale(optional) - Force the locale for formatting.
- style(optional) - Use default date/time formatting of the country specified by the locale. Possible values: SHORT (default), MEDIUM, LONG, FULL . See DateFormat for explanation.
- dateStyle(optional) - Set separate- stylefor the date part.
- timeStyle(optional) - Set separate- stylefor the time part.
Source