001    // Copyright 2006, 2007, 2008, 2009, 2010, 2011 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    
015    package org.apache.tapestry5.internal.transform;
016    
017    import org.apache.tapestry5.ComponentResources;
018    import org.apache.tapestry5.annotations.Component;
019    import org.apache.tapestry5.annotations.MixinClasses;
020    import org.apache.tapestry5.annotations.Mixins;
021    import org.apache.tapestry5.internal.InternalConstants;
022    import org.apache.tapestry5.internal.KeyValue;
023    import org.apache.tapestry5.internal.TapestryInternalUtils;
024    import org.apache.tapestry5.ioc.Location;
025    import org.apache.tapestry5.ioc.Orderable;
026    import org.apache.tapestry5.ioc.internal.services.StringLocation;
027    import org.apache.tapestry5.ioc.internal.util.CollectionFactory;
028    import org.apache.tapestry5.ioc.internal.util.InternalUtils;
029    import org.apache.tapestry5.ioc.internal.util.TapestryException;
030    import org.apache.tapestry5.model.ComponentModel;
031    import org.apache.tapestry5.model.MutableComponentModel;
032    import org.apache.tapestry5.model.MutableEmbeddedComponentModel;
033    import org.apache.tapestry5.plastic.*;
034    import org.apache.tapestry5.services.ComponentClassResolver;
035    import org.apache.tapestry5.services.transform.ComponentClassTransformWorker2;
036    import org.apache.tapestry5.services.transform.TransformationSupport;
037    
038    import java.util.List;
039    
040    /**
041     * Finds fields with the {@link org.apache.tapestry5.annotations.Component} annotation and updates
042     * the model. Also
043     * checks for the {@link Mixins} and {@link MixinClasses} annotations and uses them to update the {@link ComponentModel}
044     * .
045     */
046    public class ComponentWorker implements ComponentClassTransformWorker2
047    {
048        private final ComponentClassResolver resolver;
049    
050        public ComponentWorker(ComponentClassResolver resolver)
051        {
052            this.resolver = resolver;
053        }
054    
055        public void transform(PlasticClass plasticClass, TransformationSupport support, MutableComponentModel model)
056        {
057            for (PlasticField field : plasticClass.getFieldsWithAnnotation(Component.class))
058            {
059                transformField(plasticClass, model, field);
060            }
061        }
062    
063        private void transformField(PlasticClass transformation, MutableComponentModel model, PlasticField field)
064        {
065            Component annotation = field.getAnnotation(Component.class);
066    
067            field.claim(annotation);
068    
069            String annotationId = annotation.id();
070    
071            String fieldName = field.getName();
072    
073            String id = InternalUtils.isNonBlank(annotationId) ? annotationId : InternalUtils.stripMemberName(fieldName);
074    
075            String type = field.getTypeName();
076    
077            Location location = new StringLocation(String.format("%s.%s", transformation.getClassName(), fieldName), 0);
078    
079            MutableEmbeddedComponentModel embedded = model.addEmbeddedComponent(id, annotation.type(), type, annotation
080                    .inheritInformalParameters(), location);
081    
082            addParameters(embedded, annotation.parameters());
083    
084            updateModelWithPublishedParameters(embedded, annotation);
085    
086            convertAccessToField(field, id);
087    
088            addMixinClasses(field, embedded);
089            addMixinTypes(field, embedded);
090        }
091    
092        private void convertAccessToField(PlasticField field, String id)
093        {
094            String fieldName = field.getName();
095    
096            ComputedValue<FieldConduit<Object>> computedConduit = createProviderForEmbeddedComponentConduit(fieldName, id);
097    
098            field.setComputedConduit(computedConduit);
099        }
100    
101        private ComputedValue<FieldConduit<Object>> createProviderForEmbeddedComponentConduit(final String fieldName,
102                                                                                              final String id)
103        {
104            return new ComputedValue<FieldConduit<Object>>()
105            {
106                public FieldConduit<Object> get(InstanceContext context)
107                {
108                    final ComponentResources resources = context.get(ComponentResources.class);
109    
110                    return new ReadOnlyComponentFieldConduit(resources, fieldName)
111                    {
112                        public Object get(Object instance, InstanceContext context)
113                        {
114                            return resources.getEmbeddedComponent(id);
115                        }
116                    };
117                }
118            };
119        }
120    
121        private void updateModelWithPublishedParameters(MutableEmbeddedComponentModel embedded, Component annotation)
122        {
123            String names = annotation.publishParameters();
124    
125            if (InternalUtils.isNonBlank(names))
126            {
127                List<String> published = CollectionFactory.newList(TapestryInternalUtils.splitAtCommas(names));
128                embedded.setPublishedParameters(published);
129            }
130    
131        }
132    
133        private void addMixinClasses(PlasticField field, MutableEmbeddedComponentModel model)
134        {
135            MixinClasses annotation = field.getAnnotation(MixinClasses.class);
136    
137            if (annotation == null)
138                return;
139    
140            boolean orderEmpty = annotation.order().length == 0;
141    
142            if (!orderEmpty && annotation.order().length != annotation.value().length)
143                throw new TapestryException(TransformMessages.badMixinConstraintLength(annotation, field.getName()), model,
144                        null);
145    
146            for (int i = 0; i < annotation.value().length; i++)
147            {
148                String[] constraints = orderEmpty ? InternalConstants.EMPTY_STRING_ARRAY : TapestryInternalUtils
149                        .splitMixinConstraints(annotation.order()[i]);
150    
151                model.addMixin(annotation.value()[i].getName(), constraints);
152            }
153        }
154    
155        private void addMixinTypes(PlasticField field, MutableEmbeddedComponentModel model)
156        {
157            Mixins annotation = field.getAnnotation(Mixins.class);
158    
159            if (annotation == null)
160                return;
161    
162            for (String typeName : annotation.value())
163            {
164                Orderable<String> typeAndOrder = TapestryInternalUtils.mixinTypeAndOrder(typeName);
165                String mixinClassName = resolver.resolveMixinTypeToClassName(typeAndOrder.getTarget());
166                model.addMixin(mixinClassName, typeAndOrder.getConstraints());
167            }
168        }
169    
170        private void addParameters(MutableEmbeddedComponentModel embedded, String[] parameters)
171        {
172            for (String parameter : parameters)
173            {
174                KeyValue kv = TapestryInternalUtils.parseKeyValue(parameter);
175    
176                embedded.addParameter(kv.getKey(), kv.getValue());
177            }
178        }
179    }