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.param.validate.perspec;
021
022import java.lang.annotation.Annotation;
023import java.util.ArrayList;
024import java.util.List;
025
026import org.apache.isis.applib.annotation.MustSatisfy;
027import org.apache.isis.applib.spec.Specification;
028import org.apache.isis.core.metamodel.facetapi.Facet;
029import org.apache.isis.core.metamodel.facetapi.FacetHolder;
030import org.apache.isis.core.metamodel.facetapi.FacetUtil;
031import org.apache.isis.core.metamodel.facetapi.FeatureType;
032import org.apache.isis.core.metamodel.facets.Annotations;
033import org.apache.isis.core.metamodel.facets.FacetFactoryAbstract;
034
035public class MustSatisfySpecificationOnParameterFacetFactory extends FacetFactoryAbstract {
036
037    public MustSatisfySpecificationOnParameterFacetFactory() {
038        super(FeatureType.PARAMETERS_ONLY);
039    }
040
041    @Override
042    public void processParams(final ProcessParameterContext processParameterContext) {
043        final java.lang.annotation.Annotation[] parameterAnnotations = Annotations.getParameterAnnotations(processParameterContext.getMethod())[processParameterContext.getParamNum()];
044
045        for (final Annotation parameterAnnotation : parameterAnnotations) {
046            if (parameterAnnotation instanceof MustSatisfy) {
047                final MustSatisfy annotation = (MustSatisfy) parameterAnnotation;
048                FacetUtil.addFacet(create(annotation, processParameterContext.getFacetHolder()));
049                return;
050            }
051        }
052    }
053
054    private Facet create(final MustSatisfy annotation, final FacetHolder holder) {
055        if (annotation == null) {
056            return null;
057        }
058        final Class<?>[] values = annotation.value();
059        final List<Specification> specifications = new ArrayList<Specification>();
060        for (final Class<?> value : values) {
061            final Specification specification = newSpecificationElseNull(value);
062            if (specification != null) {
063                specifications.add(specification);
064            }
065        }
066        return specifications.size() > 0 ? new MustSatisfySpecificationOnParameterFacet(specifications, holder) : null;
067    }
068
069    private static Specification newSpecificationElseNull(final Class<?> value) {
070        if (!(Specification.class.isAssignableFrom(value))) {
071            return null;
072        }
073        try {
074            return (Specification) value.newInstance();
075        } catch (final InstantiationException e) {
076            return null;
077        } catch (final IllegalAccessException e) {
078            return null;
079        }
080    }
081
082}