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 */
019package org.apache.isis.extensions.secman.api.permission;
020
021import java.util.Collection;
022
023import org.apache.isis.commons.internal.base._NullSafe;
024import org.apache.isis.core.metamodel.services.appfeat.ApplicationFeatureId;
025
026public abstract class PermissionsEvaluationServiceAbstract implements PermissionsEvaluationService {
027
028    private static final long serialVersionUID = 1L;
029
030    @Override
031    public ApplicationPermissionValueSet.Evaluation evaluate(
032            final ApplicationFeatureId targetMemberId,
033            final ApplicationPermissionMode mode,
034            final Collection<ApplicationPermissionValue> permissionValues) {
035
036        if(_NullSafe.isEmpty(permissionValues)) {
037            return null;
038        }
039
040        final Collection<ApplicationPermissionValue> ordered = ordered(permissionValues);
041
042        for (final ApplicationPermissionValue permissionValue : ordered) {
043            if(permissionValue.implies(targetMemberId, mode)) {
044                return new ApplicationPermissionValueSet.Evaluation(permissionValue, true);
045            } else if(permissionValue.refutes(targetMemberId, mode)) {
046                return new ApplicationPermissionValueSet.Evaluation(permissionValue, false);
047            }
048        }
049        return null;
050    }
051
052    protected abstract Collection<ApplicationPermissionValue> ordered(
053            Collection<ApplicationPermissionValue> permissionValues);
054
055}