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.members.describedas.annotation;
021
022import java.util.Properties;
023
024import org.apache.isis.applib.annotation.DescribedAs;
025import org.apache.isis.core.metamodel.facetapi.FacetHolder;
026import org.apache.isis.core.metamodel.facetapi.FacetUtil;
027import org.apache.isis.core.metamodel.facetapi.FeatureType;
028import org.apache.isis.core.metamodel.facets.Annotations;
029import org.apache.isis.core.metamodel.facets.ContributeeMemberFacetFactory;
030import org.apache.isis.core.metamodel.facets.FacetFactoryAbstract;
031import org.apache.isis.core.metamodel.facets.describedas.DescribedAsFacet;
032import org.apache.isis.core.metamodel.spec.ObjectSpecification;
033
034public class DescribedAsOnMemberFacetFactory extends FacetFactoryAbstract implements ContributeeMemberFacetFactory {
035
036    public DescribedAsOnMemberFacetFactory() {
037        super(FeatureType.MEMBERS);
038    }
039
040    @Override
041    public void process(final ProcessMethodContext processMethodContext) {
042
043        DescribedAsFacet facet = createFromMetadataPropertiesIfPossible(processMethodContext);
044        
045        if(facet == null) {
046            facet = createFromAnnotationIfPossible(processMethodContext);
047        }
048        if (facet == null) {
049            facet = createFromAnnotationOnReturnTypeIfPossible(processMethodContext);
050        }
051        
052        // no-op if null
053        FacetUtil.addFacet(facet);
054    }
055
056    @Override
057    public void process(ProcessContributeeMemberContext processMemberContext) {
058        DescribedAsFacet facet = createFromMetadataPropertiesIfPossible(processMemberContext);
059        // no-op if null
060        FacetUtil.addFacet(facet);
061    }
062    
063    private static DescribedAsFacet createFromMetadataPropertiesIfPossible(
064            final ProcessContextWithMetadataProperties<? extends FacetHolder> pcwmp) {
065        
066        final FacetHolder holder = pcwmp.getFacetHolder();
067        
068        final Properties properties = pcwmp.metadataProperties("describedAs");
069        return properties != null ? new DescribedAsFacetOnMemberFromProperties(properties, holder) : null;
070    }
071    
072    private static DescribedAsFacet createFromAnnotationIfPossible(final ProcessMethodContext processMethodContext) {
073        // look for annotation on the property
074        final DescribedAs annotation = Annotations.getAnnotation(processMethodContext.getMethod(), DescribedAs.class);
075        return annotation == null ? null : new DescribedAsFacetOnMemberAnnotation(annotation.value(), processMethodContext.getFacetHolder());
076    }
077
078    private DescribedAsFacet createFromAnnotationOnReturnTypeIfPossible(final ProcessMethodContext processMethodContext) {
079        final Class<?> returnType = processMethodContext.getMethod().getReturnType();
080        final DescribedAsFacet returnTypeDescribedAsFacet = getDescribedAsFacet(returnType);
081        return returnTypeDescribedAsFacet != null ? new DescribedAsFacetForMemberDerivedFromType(returnTypeDescribedAsFacet, processMethodContext.getFacetHolder()) : null;
082    }
083    
084    private DescribedAsFacet getDescribedAsFacet(final Class<?> type) {
085        final ObjectSpecification paramTypeSpec = getSpecificationLoader().loadSpecification(type);
086        return paramTypeSpec.getFacet(DescribedAsFacet.class);
087    }
088}