    001    // Copyright 2007, 2008, 2011 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.ioc.annotations.UsesMappedConfiguration;
    018    import org.apache.tapestry5.ioc.annotations.UsesOrderedConfiguration;
    019    import org.apache.tapestry5.ioc.services.PropertyAdapter;
    020
    021    /**
    022     * Used by {@link BeanModelSource} to identify the type of data associated with a particular property (represented as a
    023     * {@link PropertyAdapter}). The data type is a string used to determine what kind of interface to use for displaying
    024     * the value of the property, or what kind of interface to use for editing the value of the property. Common property
    025     * types are "text", "enum", "checkbox", but the list is extensible.
    026     * <p/>
    027     * Different strategies for identifying the data type are encapsulated in the DataTypeAnalyzer service, forming a
    028     * chain of command.
    029     * <p/>
    030     * The DefaultDataTypeAnalyzer service maps property types to data type names.
    031     * <p/>
    032     * The DataTypeAnalyzer service is an extensible {@linkplain org.apache.tapestry5.ioc.services.ChainBuilder chain of
    033     * command}), that (by default) includes {@link org.apache.tapestry5.internal.services.AnnotationDataTypeAnalyzer} and
    034     * the {@link org.apache.tapestry5.internal.services.DefaultDataTypeAnalyzer} service (ordered last).   It uses an ordered configuration.
    035     *
    036     * @see org.apache.tapestry5.corelib.components.Grid
    037     * @see org.apache.tapestry5.corelib.components.BeanEditForm
    038     * @see BeanBlockSource
    039     */
    040    @UsesOrderedConfiguration(DataTypeAnalyzer.class)
    041    @UsesMappedConfiguration(key = Class.class, value = String.class)
    042    public interface DataTypeAnalyzer
    043    {
    044        /**
    045         * Identifies the data type, if known, or returns null if not known.
    046         */
    047        String identifyDataType(PropertyAdapter adapter);
    048    }