Example of rather simple JSF converter to transform string with separated by semicolon words to the list of strings. In my case it was useful for mailbox application for email address input field with multiple email addresses.
/**
* Custom converter to transform input string value to the list of strings.
*
* @author Maxim Baev
*/
@FacesConverter(value = "stringListConverter")
public class StringListConverter implements Converter {
private static final Logger LOGGER = LoggerFactory.getLogger(StringListConverter.class);
private static final String DELIMITER = ";";
private static final String WHITESPACE = " ";
/**
* {@inheritDoc}
*/
@Override
public Object getAsObject(final FacesContext context, final UIComponent component, final String value) {
if (value == null || value.isEmpty()) {
return null;
}
try {
return Arrays.asList(value.replaceAll(WHITESPACE, StringUtils.EMPTY).split(DELIMITER));
} catch (Exception e) {
LOGGER.error("Failed to convert string to list", e);
throw new ConverterException(new FacesMessage(String.format("Cannot convert %s to list", value)), e);
}
}
/**
* {@inheritDoc}
*/
@Override
public String getAsString(final FacesContext context, final UIComponent component, final Object value) {
if (!(value instanceof List)) {
return null;
}
return StringUtils.join((List) value, DELIMITER + WHITESPACE);
}
}
