001// Copyright 2007, 2008 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.services.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}