001// Copyright 2007, 2008 The Apache Software Foundation
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
007//     http://www.apache.org/licenses/LICENSE-2.0
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.
015package org.apache.tapestry5.services;
017import org.apache.tapestry5.FieldValidator;
018import org.apache.tapestry5.ioc.AnnotationProvider;
019import org.apache.tapestry5.ioc.annotations.UsesOrderedConfiguration;
021import java.util.List;
024 * Invoked to generate a list of validation constraint strings for a property. This typically involves scanning the
025 * property for annotations or naming conventions that confer the desired validation. The constraint strings are
026 * ultimately handed to {@link FieldValidatorSource#createValidator(org.apache.tapestry5.Field, String, String, String,
027 * org.apache.tapestry5.ioc.Messages, java.util.Locale)}.
028 */
030public interface ValidationConstraintGenerator
032    /**
033     * For a given property, identify all the approprite validation constraints. Each returned value is the name of a
034     * validator (i.e., "required") or a validator name and configuration (i.e., "minlength=5"). These contraints are
035     * exactly the individual terms in a {@link FieldValidatorSource#createValidators(org.apache.tapestry5.Field,
036     * String) validate specification}. These will ultimately be used to create {@link FieldValidator}s for the field
037     * that edits the property.
038     *
039     * @param propertyType       the type of the property for which constraints are needed
040     * @param annotationProvider provides access to any annotations concerning the property (for implementations that
041     *                           are based on analysis of property annotations)
042     * @return a list of constraints
043     * @see FieldValidatorSource
044     */
045    List<String> buildConstraints(Class propertyType, AnnotationProvider annotationProvider);