001// Copyright 2010 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.validator;
016
017import org.apache.tapestry5.ioc.annotations.UsesMappedConfiguration;
018
019/**
020 * Allows support for "validator macros", a simple-minded way of combining several related valiations together under
021 * a single name. The service's configuration maps string keys (macro names) to string values (validation constraints).
022 * 
023 * @since 5.2.0
024 */
025@UsesMappedConfiguration(String.class)
026public interface ValidatorMacro
027{
028    /**
029     * Given a <em>potential</em> validator macro (a simple string name), returns the value for that macro, a
030     * comma-separated list of validation constraints.
031     * 
032     * @return constraints, or null if no such validator macro
033     */
034    String valueForMacro(String validatorMacro);
035}