    001    // Copyright 2007 The Apache Software Foundation
    002    //
    003    // Licensed under the Apache License, Version 2.0 (the "License");
    004    // you may not use this file except in compliance with the License.
    005    // You may obtain a copy of the License at
    006    //
    007    //     http://www.apache.org/licenses/LICENSE-2.0
    008    //
    009    // Unless required by applicable law or agreed to in writing, software
    010    // distributed under the License is distributed on an "AS IS" BASIS,
    011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    012    // See the License for the specific language governing permissions and
    013    // limitations under the License.
    014
    015    package org.apache.tapestry5.services;
    016
    017    import org.apache.tapestry5.corelib.components.Grid;
    018    import org.apache.tapestry5.ioc.Messages;
    019
    020    /**
    021     * Provides context information needed when displaying a value. This interface is an integral part of the {@link Grid}
    022     * and similar output components.    It is made available to components via an {@link
    023     * org.apache.tapestry5.annotations.Environmental} annotation.
    024     */
    025    public interface PropertyOutputContext
    026    {
    027        /**
    028         * Returns the value of the property (the object being displayed is encapsulated by the context).
    029         */
    030        Object getPropertyValue();
    031
    032        /**
    033         * Returns the message catalog appropriate for use. In practice, this is the message catalog of the container of the
    034         * {@link Grid} component. This is used, for example, to locate labels for fields, or to locate string
    035         * representations of Enums.
    036         */
    037        Messages getMessages();
    038
    039        /**
    040         * Returns a string that identifies the property, usually the property name. This is used as the basis for the
    041         * client-side client id.
    042         */
    043        String getPropertyId();
    044
    045        /**
    046         * Returns the name of the property (which may, in fact, be a property expression).
    047         */
    048        String getPropertyName();
    049    }