http://www.opensymphony.com/webwork/api/com/opensymphony/xwork/util/XWorkBasicConverter.html


XWork will automatically handle the most common type conversion for you.
This includes support for converting to and from Strings for each of the following:

• String
• boolean / Boolean
• char / Character
• int / Integer, float / Float, long / Long, double / Double
• dates - uses the SHORT or RFC3339 format (yyyy-MM-dd'T'HH:mm:ss) for the Locale associated with the current request
• arrays - assuming the individual strings can be coverted to the individual items
• collections - if not object type can be determined, it is assumed to be a String and a new ArrayList is created

Note: that with arrays the type conversion will defer to the type of the array elements and try to convert each item individually. As with any other type conversion, if the conversion can't be performed the standard type conversion error reporting is used to indicate a problem occured while processing the type conversion.