    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
    015package org.apache.tapestry5.services;
    016
    017import org.apache.tapestry5.commons.Messages;
    018import org.apache.tapestry5.corelib.components.Grid;
    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 */
    025public 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}