org.apache.tapestry5
Interface FieldTranslator<T>

All Known Implementing Classes:

FieldTranslatorImpl

public interface FieldTranslator<T>

A wrapper around Translator that combines the translator for a specific Field and (sometimes) an override of the default validation message (used when an input value can't be parsed).

Method Summary

Class<T>	getType() Returns the type of the server-side value.
T	parse(String input) Invoked after the client-submitted value has been translated to check that the value conforms to expectations (often, in terms of minimum or maximum value).
void	render(MarkupWriter writer) Invokes Translator.render(Field, String, MarkupWriter,org.apache.tapestry5.services.FormSupport).
String	toClient(T value) Converts a server-side value to a client-side string.

Method Detail

getType

Class<T> getType()

Returns the type of the server-side value.

Returns:

a type

parse

T parse(String input)
        throws ValidationException

Invoked after the client-submitted value has been translated to check that the value conforms to expectations (often, in terms of minimum or maximum value). If and only if the value is approved by all Validators is the value applied by the field.

Throws:

ValidationException - if the value violates the constraint

toClient

String toClient(T value)

Converts a server-side value to a client-side string. This allows for formatting of the value in a way appropriate to the end user.

Parameters:

value - the server side value (which will not be null)

Returns:

client-side value to present to the user

See Also:

Translator.toClient(Object)

render

void render(MarkupWriter writer)

Invokes Translator.render(Field, String, MarkupWriter,org.apache.tapestry5.services.FormSupport). This is called at a point "inside" the tag, so that additional attributes may be added. In many cases, the underlying Validator may write client-side JavaScript to enforce the constraint as well.

Parameters:

writer - markup writer to direct output to.

See Also:

MarkupWriter.attributes(Object[])