    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
    015package org.apache.tapestry5.internal.transform;
    016
    017import org.apache.tapestry5.ComponentResources;
    018import org.apache.tapestry5.annotations.Component;
    019import org.apache.tapestry5.annotations.MixinClasses;
    020import org.apache.tapestry5.annotations.Mixins;
    021import org.apache.tapestry5.internal.InternalConstants;
    022import org.apache.tapestry5.internal.KeyValue;
    023import org.apache.tapestry5.internal.TapestryInternalUtils;
    024import org.apache.tapestry5.ioc.Location;
    025import org.apache.tapestry5.ioc.Orderable;
    026import org.apache.tapestry5.ioc.internal.services.StringLocation;
    027import org.apache.tapestry5.ioc.internal.util.CollectionFactory;
    028import org.apache.tapestry5.ioc.internal.util.InternalUtils;
    029import org.apache.tapestry5.ioc.internal.util.TapestryException;
    030import org.apache.tapestry5.model.ComponentModel;
    031import org.apache.tapestry5.model.MutableComponentModel;
    032import org.apache.tapestry5.model.MutableEmbeddedComponentModel;
    033import org.apache.tapestry5.plastic.*;
    034import org.apache.tapestry5.services.ComponentClassResolver;
    035import org.apache.tapestry5.services.transform.ComponentClassTransformWorker2;
    036import org.apache.tapestry5.services.transform.TransformationSupport;
    037
    038import 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 */
    046public 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(String.format("%d mixins defined via @MixinClasses on field '%s', but %d ordering constraints \\\n" +
    144                    " specified (expected 0 or %1$d).", annotation.value().length, field.getName(), annotation.order().length), model,
    145                    null);
    146
    147        for (int i = 0; i < annotation.value().length; i++)
    148        {
    149            String[] constraints = orderEmpty ? InternalConstants.EMPTY_STRING_ARRAY : TapestryInternalUtils
    150                    .splitMixinConstraints(annotation.order()[i]);
    151
    152            model.addMixin(annotation.value()[i].getName(), constraints);
    153        }
    154    }
    155
    156    private void addMixinTypes(PlasticField field, MutableEmbeddedComponentModel model)
    157    {
    158        Mixins annotation = field.getAnnotation(Mixins.class);
    159
    160        if (annotation == null)
    161            return;
    162
    163        for (String typeName : annotation.value())
    164        {
    165            Orderable<String> typeAndOrder = TapestryInternalUtils.mixinTypeAndOrder(typeName);
    166            String mixinClassName = resolver.resolveMixinTypeToClassName(typeAndOrder.getTarget());
    167            model.addMixin(mixinClassName, typeAndOrder.getConstraints());
    168        }
    169    }
    170
    171    private void addParameters(MutableEmbeddedComponentModel embedded, String[] parameters)
    172    {
    173        for (String parameter : parameters)
    174        {
    175            KeyValue kv = TapestryInternalUtils.parseKeyValue(parameter);
    176
    177            embedded.addParameter(kv.getKey(), kv.getValue());
    178        }
    179    }
    180}