001/**
002 *  Licensed to the Apache Software Foundation (ASF) under one or more
003 *  contributor license agreements.  See the NOTICE file distributed with
004 *  this work for additional information regarding copyright ownership.
005 *  The ASF licenses this file to You under the Apache License, Version 2.0
006 *  (the "License"); you may not use this file except in compliance with
007 *  the License.  You may obtain a copy of the License at
008 *
009 *     http://www.apache.org/licenses/LICENSE-2.0
010 *
011 *  Unless required by applicable law or agreed to in writing, software
012 *  distributed under the License is distributed on an "AS IS" BASIS,
013 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 *  See the License for the specific language governing permissions and
015 *  limitations under the License.
016 */
017package org.apache.isis.viewer.restfulobjects.rendering.domainobjects;
018
019import javax.ws.rs.core.MediaType;
020
021import org.apache.isis.core.metamodel.adapter.ObjectAdapter;
022import org.apache.isis.core.metamodel.facets.object.encodeable.EncodableFacet;
023import org.apache.isis.core.metamodel.spec.ObjectSpecification;
024import org.apache.isis.viewer.restfulobjects.applib.JsonRepresentation;
025import org.apache.isis.viewer.restfulobjects.applib.Rel;
026import org.apache.isis.viewer.restfulobjects.applib.RepresentationType;
027import org.apache.isis.viewer.restfulobjects.rendering.LinkFollowSpecs;
028import org.apache.isis.viewer.restfulobjects.rendering.RendererContext;
029import org.apache.isis.viewer.restfulobjects.rendering.ReprRendererAbstract;
030import org.apache.isis.viewer.restfulobjects.rendering.ReprRendererException;
031
032public class ScalarValueReprRenderer extends ReprRendererAbstract<ScalarValueReprRenderer, ObjectAdapter> {
033
034    private ObjectSpecification returnType;
035
036    ScalarValueReprRenderer(final RendererContext resourceContext, final LinkFollowSpecs linkFollower, final JsonRepresentation representation) {
037        super(resourceContext, linkFollower, null, representation); // null for representationType (there is none)
038    }
039
040    /**
041     * Fail early...
042     * 
043     * <p>
044     * In case I forget in the future that scalar values don't have a representation.  
045     */
046    @Override
047    public MediaType getMediaType() {
048        throw new UnsupportedOperationException("no mediaType defined for scalar values");
049    }
050    
051    @Override
052    public ScalarValueReprRenderer with(final ObjectAdapter objectAdapter) {
053        final EncodableFacet facet = objectAdapter.getSpecification().getFacet(EncodableFacet.class);
054        if (facet == null) {
055            throw ReprRendererException.create("Not an (encodable) value", objectAdapter.titleString());
056        }
057        final Object value = JsonValueEncoder.asObject(objectAdapter);
058
059        representation.mapPut("value", value);
060        return this;
061    }
062    
063    @Override
064    public JsonRepresentation render() {
065
066        addLinkToReturnType();
067
068        getExtensions();
069
070        return representation;
071    }
072
073    public ScalarValueReprRenderer withReturnType(final ObjectSpecification returnType) {
074        this.returnType = returnType;
075        return this;
076    }
077
078    private void addLinkToReturnType() {
079        addLink(Rel.RETURN_TYPE, returnType);
080    }
081
082}