001/*
002 *  Licensed to the Apache Software Foundation (ASF) under one
003 *  or more contributor license agreements.  See the NOTICE file
004 *  distributed with this work for additional information
005 *  regarding copyright ownership.  The ASF licenses this file
006 *  to you under the Apache License, Version 2.0 (the
007 *  "License"); you may not use this file except in compliance
008 *  with the License.  You may obtain a copy of the License at
009 *
010 *        http://www.apache.org/licenses/LICENSE-2.0
011 *
012 *  Unless required by applicable law or agreed to in writing,
013 *  software distributed under the License is distributed on an
014 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 *  KIND, either express or implied.  See the License for the
016 *  specific language governing permissions and limitations
017 *  under the License.
018 */
019
020package org.apache.isis.core.progmodel.facets.collections.sortedby;
021
022import java.util.Comparator;
023import java.util.List;
024
025import org.apache.isis.applib.annotation.SortedBy;
026import org.apache.isis.core.commons.config.IsisConfiguration;
027import org.apache.isis.core.metamodel.facetapi.FacetHolder;
028import org.apache.isis.core.metamodel.facetapi.FacetUtil;
029import org.apache.isis.core.metamodel.facetapi.FeatureType;
030import org.apache.isis.core.metamodel.facetapi.MetaModelValidatorRefiner;
031import org.apache.isis.core.metamodel.facets.Annotations;
032import org.apache.isis.core.metamodel.facets.FacetFactoryAbstract;
033import org.apache.isis.core.metamodel.facets.collections.sortedby.SortedByFacet;
034import org.apache.isis.core.metamodel.spec.ObjectSpecification;
035import org.apache.isis.core.metamodel.spec.feature.Contributed;
036import org.apache.isis.core.metamodel.spec.feature.OneToManyAssociation;
037import org.apache.isis.core.metamodel.specloader.validator.MetaModelValidatorComposite;
038import org.apache.isis.core.metamodel.specloader.validator.MetaModelValidatorVisiting;
039import org.apache.isis.core.metamodel.specloader.validator.MetaModelValidatorVisiting.Visitor;
040import org.apache.isis.core.metamodel.specloader.validator.ValidationFailures;
041
042/**
043 * There is no check that the value is a {@link Comparator}; instead this is done through 
044 * the {@link #refineMetaModelValidator(MetaModelValidatorComposite, IsisConfiguration)}.
045 */
046public class SortedByAnnotationFacetFactory extends FacetFactoryAbstract implements MetaModelValidatorRefiner {
047
048    public SortedByAnnotationFacetFactory() {
049        super(FeatureType.COLLECTIONS_ONLY);
050    }
051
052    @Override
053    public void process(final ProcessMethodContext processMethodContext) {
054        final SortedBy renderAnnotation = Annotations.getAnnotation(processMethodContext.getMethod(), SortedBy.class);
055        FacetUtil.addFacet(create(renderAnnotation, processMethodContext.getFacetHolder()));
056    }
057
058    private SortedByFacet create(final SortedBy annotation, final FacetHolder holder) {
059        if (annotation == null) {
060            return null;
061        } 
062        final Class<?> annotationValue = annotation.value();
063        @SuppressWarnings({ "rawtypes", "unchecked" })
064        final Class<? extends Comparator<?>> comparatorType = (Class)annotationValue;
065        return new SortedByFacetAnnotation(holder, comparatorType);
066    }
067
068    @Override
069    public void refineMetaModelValidator(MetaModelValidatorComposite metaModelValidator, IsisConfiguration configuration) {
070        metaModelValidator.add(new MetaModelValidatorVisiting(newValidatorVisitor()));
071    }
072
073    protected Visitor newValidatorVisitor() {
074        return new MetaModelValidatorVisiting.Visitor() {
075
076            @Override
077            public boolean visit(ObjectSpecification objectSpec, ValidationFailures validationFailures) {
078                List<OneToManyAssociation> objectCollections = objectSpec.getCollections(Contributed.EXCLUDED);
079                for (OneToManyAssociation objectCollection : objectCollections) {
080                    final SortedByFacet facet = objectCollection.getFacet(SortedByFacet.class);
081                    if(facet != null) {
082                        final Class<? extends Comparator<?>> cls = facet.value();
083                        if(!Comparator.class.isAssignableFrom(cls)) {
084                            validationFailures.add("%s#%s is annotated with @SortedBy, but the class specified '%s' is not a Comparator", objectSpec.getIdentifier().getClassName(), objectCollection.getId(), facet.value().getName());
085                        }
086                    }
087                }
088                return true;
089            }
090        };
091    }
092
093
094}