| // Copyright 2006, 2008, 2011 The Apache Software Foundation |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package org.apache.tapestry5; |
| |
| import org.apache.tapestry5.services.FormSupport; |
| |
| /** |
| * Translates between client-side and server-side values. Client-side values are always strings. |
| * |
| * @param <T> |
| * @see org.apache.tapestry5.services.TranslatorSource |
| * @see org.apache.tapestry5.FieldValidationSupport |
| * @see org.apache.tapestry5.FieldTranslator |
| */ |
| public interface Translator<T> |
| { |
| /** |
| * Returns a unique name for the translator. This is used to identify the translator by name, but is also used when |
| * locating override messages for the translator. |
| * |
| * @return unique name for the translator |
| */ |
| String getName(); |
| |
| /** |
| * 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. The output client value should be parsable by |
| * {@link #parseClient(Field, String, String)}. |
| * |
| * @param value |
| * the server side value (which will not be null) |
| * @return client-side value to present to the user |
| */ |
| String toClient(T value); |
| |
| /** |
| * Returns the type of the server-side value. |
| * |
| * @return a type |
| */ |
| Class<T> getType(); |
| |
| /** |
| * Returns the message key, within the application's global message catalog, normally used by this validator. This |
| * is used to provide the formatted message to {@link #parseClient(Field, String, String)} or |
| * {@link #render(Field, String, MarkupWriter, org.apache.tapestry5.services.FormSupport)}. |
| * |
| * @return a message key |
| */ |
| String getMessageKey(); |
| |
| /** |
| * Converts a submitted request value into an appropriate server side value. |
| * |
| * @param field |
| * for which a value is being parsed |
| * @param clientValue |
| * to convert to a server value; this will not be null, but may be blank |
| * @param message |
| * formatted validation message, either from validation messages, or from an override |
| * @return equivalent server-side value (possibly null) |
| * @throws ValidationException |
| * if the value can not be parsed |
| */ |
| T parseClient(Field field, String clientValue, String message) throws ValidationException; |
| |
| /** |
| * Hook used by components to allow the validator to contribute additional attributes or (more often) client-side |
| * JavaScript (via the |
| * {@link org.apache.tapestry5.services.FormSupport#addValidation(Field, String, String, Object)}). |
| * |
| * @param field |
| * the field which is currently being rendered |
| * @param message |
| * formatted validation message, either from validation messages, or from an override |
| * @param writer |
| * markup writer, allowing additional attributes to be written into the active element |
| * @param formSupport |
| * used to add JavaScript |
| */ |
| void render(Field field, String message, MarkupWriter writer, FormSupport formSupport); |
| } |