    001    // Copyright 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.services;
    016
    017    import org.apache.tapestry5.ioc.AnnotationProvider;
    018    import org.apache.tapestry5.ioc.ObjectLocator;
    019    import org.apache.tapestry5.ioc.ObjectProvider;
    020
    021    /**
    022     * Provides a single object of a given type.
    023     *
    024     * @since 5.3
    025     */
    026    public class StaticObjectProvider<S> implements ObjectProvider
    027    {
    028        private final Class<S> valueType;
    029
    030        private final S value;
    031
    032        public StaticObjectProvider(Class<S> valueType, S value)
    033        {
    034            this.valueType = valueType;
    035            this.value = value;
    036
    037            assert valueType != null;
    038            assert value != null;
    039        }
    040
    041
    042        public <T> T provide(Class<T> objectType, AnnotationProvider annotationProvider, ObjectLocator locator)
    043        {
    044            if (objectType == valueType)
    045            {
    046                return objectType.cast(value);
    047            }
    048
    049            return null;
    050        }
    051    }