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.properties.event;
021
022import com.google.common.base.Objects;
023import com.google.common.collect.Lists;
024
025import org.apache.isis.applib.FatalException;
026import org.apache.isis.applib.Identifier;
027import org.apache.isis.applib.services.eventbus.EventBusService;
028import org.apache.isis.applib.services.eventbus.PropertyChangedEvent;
029import org.apache.isis.core.metamodel.adapter.ObjectAdapter;
030import org.apache.isis.core.metamodel.facetapi.Facet;
031import org.apache.isis.core.metamodel.facetapi.FacetHolder;
032import org.apache.isis.core.metamodel.facets.accessor.PropertyOrCollectionAccessorFacet;
033import org.apache.isis.core.metamodel.facets.properties.event.PostsPropertyChangedEventSetterFacet;
034import org.apache.isis.core.metamodel.facets.properties.event.PostsPropertyChangedEventSetterFacetAbstract;
035import org.apache.isis.core.metamodel.facets.properties.modify.PropertySetterFacet;
036import org.apache.isis.core.metamodel.runtimecontext.ServicesInjector;
037
038public class PostsPropertyChangedEventSetterFacetAnnotation 
039        extends PostsPropertyChangedEventSetterFacetAbstract {
040
041    private final PropertyOrCollectionAccessorFacet getterFacet;
042    private final PropertySetterFacet setterFacet;
043    
044    private final Helper helper;
045    
046    public PostsPropertyChangedEventSetterFacetAnnotation(
047            final Class<? extends PropertyChangedEvent<?, ?>> eventType, 
048            final PropertyOrCollectionAccessorFacet getterFacet, 
049            final PropertySetterFacet setterFacet, 
050            final ServicesInjector servicesInjector,
051            final FacetHolder holder) {
052        super(eventType, holder);
053        this.getterFacet = getterFacet;
054        this.setterFacet = setterFacet;
055        this.helper = new Helper(servicesInjector);
056    }
057
058    @Override
059    public void setProperty(ObjectAdapter targetAdapter, ObjectAdapter valueAdapter) {
060        if(setterFacet == null) {
061            return;
062        }
063        if(helper.getEventBusService() == null) {
064            setterFacet.setProperty(targetAdapter, valueAdapter);
065            return;
066        }
067        
068        final Object oldValue = getterFacet.getProperty(targetAdapter);
069        setterFacet.setProperty(targetAdapter, valueAdapter);
070        final Object newValue = getterFacet.getProperty(targetAdapter);
071        postEventIfChanged(targetAdapter, getIdentified().getIdentifier(), oldValue, newValue);
072    }
073
074    @SuppressWarnings({ "rawtypes", "unchecked" })
075    private void postEventIfChanged(
076            final ObjectAdapter targetAdapter, 
077            final Identifier identifier, 
078            final Object oldValue, 
079            final Object newValue) {
080        
081        if(Objects.equal(oldValue, newValue)) {
082            // do nothing.
083            return;
084        }
085        try {
086            final Class type = value();
087            final Object source = ObjectAdapter.Util.unwrap(targetAdapter);
088            final PropertyChangedEvent<?, ?> event = Util.newEvent(type, source, identifier, oldValue, newValue);
089
090            helper.postEvent(event);
091        } catch (Exception e) {
092            throw new FatalException(e);
093        }
094    }
095
096    
097    // //////////////////////////////////////
098    // MultiTypedFacet
099    // //////////////////////////////////////
100
101    @SuppressWarnings("unchecked")
102    @Override
103    public Class<? extends Facet>[] facetTypes() {
104        return Lists.newArrayList(
105                    type(),
106                    PostsPropertyChangedEventSetterFacet.class
107                ).toArray(new Class[]{});
108    }
109
110    @SuppressWarnings("unchecked")
111    @Override
112    public <T extends Facet> T getFacet(Class<T> facet) {
113        return (T) this;
114    }
115
116
117}