Wicket ValidationError not using IConverters specified in Application

Question

I'm trying to localize validation error messages with Wicket and ran into this situation. I use custom converters to convert date values to the desired format (see below). However, when using AbstractValidator and IValidationError the values are not converted correctly. Default conversion - probably #toString() - is used instead.

Desired error message "... 20.12.2012"

Actual error message "... 2012-12-20"

We use Joda-time to handle date and time values in our model. We also want that the dates and times are shown in Finnish locale no matter which language is shown to the user, i.e., dates are shown as d.m.yyyy and time as hh:mm.

In my Application class I have specified two type converters, one for LocalDate and one for LocalTime. Normally, both converters work fine. I.e., new Label("id", new LocalDate(2013, 5, 7)); shows as "7.5.2013". Furthermore, the conversion works great with message interpolation and StringResourceModels. E.g. a property prop=The date was: ${date} is shown correctly as "The date was 20.12.2012".

The date validation logic is done in the business layer, where exception is thrown for a validation error. The exception might contain variables that need to be shown as feedback to the user. Following is a simplified example of the situation.

The Application class

@Override
protected IConverterLocator newConverterLocator() {
    final ConverterLocator locator = new ConverterLocator();
    locator.set(LocalDate.class, new LocalDateConverter());
    locator.set(LocalTime.class, new LocalTimeConverter());
    return locator;
}

The Validator class

public class MyDateValidator extends AbstractValidator<LocalDate> {
...
@Override
protected void onValidate(IValidatable<LocalDate> validatable) {
    try {
        service.validateDate(validatable.getValue());
    } catch (MyValidationException e) {
        Map<String, Object> values = new HashMap<String, Object>();
        values.put("date", e.getDate());
        error(validatable, "DateValidator", values);
    }
}

The converted properties

DateValidator=There was an error on ${date}

EDIT:

The culprit seems to be MapVariableInterpolator#getValue(variableName) which uses Strings.toString which in turns calls object.toString(). Still need to find out how it normally works.

score 1 · Accepted Answer · answered Nov 22 '12 at 12:33

Seems it is a bug with Wicket that is fixed in version 6.0.0, but not in 1.5 (https://issues.apache.org/jira/browse/WICKET-4608). Since we cannot migrate to wicket 6 straight away, we needed to implement a fix ourselves. Currently, it converts the variables to String objects by using the Application's converters.

@SuppressWarnings("unchecked")
public static <T> String convert(T value) {
    return Application.get().getConverterLocator().<T>getConverter((Class<T>) value.getClass())
            .convertToString(value, Session.get().getLocale());
}

Wicket ValidationError not using IConverters specified in Application

The Application class

The Validator class

The converted properties

1 Answers1