    001// Copyright 2007-2013 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.Block;
    018import org.apache.tapestry5.ioc.annotations.UsesConfiguration;
    019
    020/**
    021 * A source of {@link Block}s used to display the properties of a bean (used by the {@link
    022 * org.apache.tapestry5.corelib.components.Grid} component), or to edit the properties of a bean (used by the {@link
    023 * org.apache.tapestry5.corelib.components.BeanEditForm} component). Contributions to this service (a configuration of
    024 * {@link BeanBlockContribution}s) define what properties may be editted.
    025 * <p/>
    026 * Blocks are accessed in terms of a <strong>data type</strong> a string that identifies the type of data to be editted,
    027 * such as "string", "date", "boolean", etc.
    028 * <p/>
    029 * Tapestry contributes a number of default data types and corresponding edit and display blocks. The {@link
    030 * org.apache.tapestry5.services.BeanBlockOverrideSource} service allows these to be overridden.
    031 *
    032 * @see org.apache.tapestry5.services.DataTypeAnalyzer
    033 * @see org.apache.tapestry5.modules.TapestryModule#provideDefaultBeanBlocks(org.apache.tapestry5.ioc.Configuration)
    034 */
    035@UsesConfiguration(BeanBlockContribution.class)
    036public interface BeanBlockSource
    037{
    038    /**
    039     * Returns a block which can be used to render an editor for the given data type, in the form of a field label and
    040     * input field.
    041     *
    042     * @param datatype logical name for the type of data to be displayed
    043     * @return the Block
    044     * @throws RuntimeException if no appropriate block is available
    045     */
    046    Block getEditBlock(String datatype);
    047
    048    /**
    049     * Returns a block which can be used to render output for the given data type.
    050     *
    051     * @param datatype logical name for the type of data to be displayed
    052     * @return the Block
    053     * @throws RuntimeException if no appropriate block is available
    054     */
    055    Block getDisplayBlock(String datatype);
    056
    057    /**
    058     * Checks to see if there is a display block for the indicated data type.
    059     *
    060     * @param datatype to check for
    061     * @return true if a block is available
    062     */
    063    boolean hasDisplayBlock(String datatype);
    064}