    001    // Copyright 2006, 2007, 2008, 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
    015    package org.apache.tapestry5.ioc.internal;
    016
    017    import java.util.Collection;
    018
    019    import org.apache.tapestry5.ioc.Configuration;
    020    import org.apache.tapestry5.ioc.ObjectLocator;
    021
    022    /**
    023     * Wraps a {@link java.util.Collection} as a {@link org.apache.tapestry5.ioc.Configuration} and perform validation that
    024     * collected value are of the correct type.
    025     */
    026    public class ValidatingConfigurationWrapper<T> extends AbstractConfigurationImpl<T> implements Configuration<T>
    027    {
    028        private final TypeCoercerProxy typeCoercer;
    029
    030        private final String serviceId;
    031
    032        private final Class<T> expectedType;
    033
    034        private final Collection<T> collection;
    035
    036        public ValidatingConfigurationWrapper(Class<T> expectedType, ObjectLocator locator, TypeCoercerProxy typeCoercer,
    037                Collection<T> collection, String serviceId)
    038        {
    039            super(expectedType, locator);
    040            this.typeCoercer = typeCoercer;
    041
    042            this.collection = collection;
    043            this.serviceId = serviceId;
    044            this.expectedType = expectedType;
    045        }
    046
    047        public void add(T object)
    048        {
    049            if (object == null)
    050                throw new NullPointerException(IOCMessages.contributionWasNull(serviceId));
    051
    052            T coerced = typeCoercer.coerce(object, expectedType);
    053
    054            collection.add(coerced);
    055        }
    056
    057        public void addInstance(Class<? extends T> clazz)
    058        {
    059            add(instantiate(clazz));
    060        }
    061    }