Module org.apache.wicket.util
Package org.apache.wicket.util.convert

Interface IConverter<C>

Type Parameters:
C - The object to convert from and to String
All Superinterfaces:
IClusterable, Serializable
All Known Implementing Classes:
AbstractConverter, AbstractDateConverter, AbstractDecimalConverter, AbstractIntegerConverter, AbstractJavaTimeConverter, AbstractNumberConverter, BigDecimalConverter, BigIntegerConverter, BooleanConverter, ByteConverter, CalendarConverter, CharacterConverter, DateConverter, DoubleConverter, FloatConverter, IntegerConverter, LocalDateConverter, LocalDateTimeConverter, LocalTimeConverter, LongConverter, MaskConverter, ShortConverter, SqlDateConverter, SqlTimeConverter, SqlTimestampConverter, ZonedDateTimeConverter
public interface IConverter<C> extends IClusterable
Converts input to output and vice versa. Converters are needed in web applications because we have to switch between Java objects on the server and Strings in the browser output and input.

Output conversion, which is handled by convertToString(Object, Locale), is typically used by components when they render, so that a date can be displayed as '12/12/2007'. Input conversion, handled by convertToObject(String, Locale), is typically used by form components to interpret incoming values Such values are strings as they are send as request parameters from browsers. An incoming value could be the string '12/12/2007' which could be translated to a corresponding Date object. Notice that incoming value, when used by a FormComponent, will never be null because before validation form components perform the required (see FormComponent.isRequired()) check which errors out on null values. In the case the FormComponent is not required and the user enters a null value converters will not be invoked because no type conversion is necessary.

See org.apache.wicket.Component#getConverter(Class) See org.apache.wicket.Application#getConverterLocator()
Author:
Eelco Hillenius, Jonathan Locke

  • Method Details

    • convertToObject

      C convertToObject(String value, Locale locale) throws ConversionException
      Converts the given String value
      Parameters:
      value - The string value to convert
      locale - The locale used to convert the value
      Returns:
      The converted value
      Throws:
      ConversionException - if value could not be converted

    • convertToString

      String convertToString(C value, Locale locale)
      Converts the given value to a string.
      Parameters:
      value - The value to convert
      locale - The locale used to convert the value
      Returns:
      The converted string value