    001// Copyright 2012 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.compatibility;
    016
    017import org.apache.tapestry5.ComponentResources;
    018
    019/**
    020 * Used to report deprecation warnings for components.
    021 *
    022 * @since 5.4
    023 */
    024public interface DeprecationWarning
    025{
    026
    027    /**
    028     * Used to identify a component parameter that has been deprecated. Typically, such parameters are simply
    029     * ignored, but the message should be specific about this.
    030     *
    031     * @param resources
    032     *         identifies the component, including its location
    033     * @param parameterName
    034     *         name of the deprecated parameter
    035     * @param message
    036     *         message to display; typically explains what action will be taken, such as simply ignoring the parameter entirely. This should clarify
    037     *         the issue to the developer, guiding them towards resolving the deprecation, typically be eliminating
    038     *         the parameter entirely.
    039     */
    040    void componentParameter(ComponentResources resources, String parameterName, String message);
    041
    042    /**
    043     * The most common case: checks to see if the parameter name is bound and if so emits a warning that the parameter
    044     * is ignored and will be removed.
    045     *
    046     * @param resources
    047     *         identifies the component, including its location
    048     * @param parameterNames
    049     *         names of the deprecated parameters
    050     */
    051    void ignoredComponentParameters(ComponentResources resources, String... parameterNames);
    052
    053    /**
    054     * Used to identify a specific parameter value that is no longer supported. The first time this combination of
    055     * component, parameter name, and parameter value are provided, an error is logged against this service's
    056     * logger, including the component type and complete id, name of parameter (but not the value), the message, and the location of
    057     * the component.
    058     *
    059     * @param resources
    060     *         identifies the component, including its location.
    061     * @param parameterName
    062     *         name of parameter containing illegal value.
    063     * @param parameterValue
    064     *         value that is not supported (typically, an enum type). May be null.
    065     * @param message
    066     *         message to display; typically explains that action will be taken, such as treating the value as an alternate value,
    067     *         or simply ignoring the value. This should clarify the issue to the developer, guiding them towards resolving
    068     *         the deprecation, by changing the value, or eliminating the use of the parameter entirely.
    069     */
    070    void componentParameterValue(ComponentResources resources, String parameterName, Object parameterValue, String message);
    071}