Converts the given object to a given type. How this is to be done is implemented in toClass. The OGNL context, o
and toClass are given. This method should be able to handle conversion in general without any context or object
convertValue in class ognl.DefaultTypeConverter
context - - OGNL context under which the conversion is being done
o - - the object to be converted
toClass - - the class that contains the code to convert to enumeration
Converted value of type declared in toClass or TypeConverter.NoConversionPossible to indicate that the
conversion was not possible.