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    
020    package org.apache.isis.core.progmodel.facets.object.value.annotation;
021    
022    import org.apache.isis.applib.annotation.Value;
023    import org.apache.isis.core.commons.config.IsisConfiguration;
024    import org.apache.isis.core.commons.lang.StringUtils;
025    import org.apache.isis.core.metamodel.facetapi.FacetHolder;
026    import org.apache.isis.core.progmodel.facets.object.value.ValueFacetAbstract;
027    import org.apache.isis.core.progmodel.facets.object.value.ValueSemanticsProviderContext;
028    import org.apache.isis.core.progmodel.facets.object.value.ValueSemanticsProviderUtil;
029    
030    public class ValueFacetAnnotation extends ValueFacetAbstract {
031    
032        private static String semanticsProviderName(final Class<?> annotatedClass, final IsisConfiguration configuration) {
033            final Value annotation = annotatedClass.getAnnotation(Value.class);
034            final String semanticsProviderName = annotation.semanticsProviderName();
035            if (!StringUtils.isNullOrEmpty(semanticsProviderName)) {
036                return semanticsProviderName;
037            }
038            return ValueSemanticsProviderUtil.semanticsProviderNameFromConfiguration(annotatedClass, configuration);
039        }
040    
041        private static Class<?> semanticsProviderClass(final Class<?> annotatedClass) {
042            final Value annotation = annotatedClass.getAnnotation(Value.class);
043            return annotation.semanticsProviderClass();
044        }
045    
046        public ValueFacetAnnotation(final Class<?> annotatedClass, final FacetHolder holder,
047            final IsisConfiguration configuration, final ValueSemanticsProviderContext context) {
048            this(semanticsProviderName(annotatedClass, configuration), semanticsProviderClass(annotatedClass), holder,
049                configuration, context);
050        }
051    
052        private ValueFacetAnnotation(final String candidateSemanticsProviderName,
053            final Class<?> candidateSemanticsProviderClass, final FacetHolder holder,
054            final IsisConfiguration configuration, final ValueSemanticsProviderContext context) {
055            super(ValueSemanticsProviderUtil.valueSemanticsProviderOrNull(candidateSemanticsProviderClass,
056                candidateSemanticsProviderName), AddFacetsIfInvalidStrategy.DO_ADD, holder, configuration, context);
057        }
058    
059        /**
060         * Always valid, even if the specified semanticsProviderName might have been wrong.
061         */
062        @Override
063        public boolean isValid() {
064            return true;
065        }
066    
067    }