    001    // Copyright 2006, 2007, 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 java.util.List;
    018
    019    import org.apache.tapestry5.ioc.services.Builtin;
    020    import org.apache.tapestry5.ioc.services.DefaultImplementationBuilder;
    021    import org.apache.tapestry5.ioc.services.PipelineBuilder;
    022    import org.apache.tapestry5.ioc.services.PlasticProxyFactory;
    023    import org.slf4j.Logger;
    024
    025    public class PipelineBuilderImpl implements PipelineBuilder
    026    {
    027
    028        private final PlasticProxyFactory proxyFactory;
    029
    030        private final DefaultImplementationBuilder defaultImplementationBuilder;
    031
    032        public PipelineBuilderImpl(@Builtin
    033        PlasticProxyFactory proxyFactory,
    034
    035        DefaultImplementationBuilder defaultImplementationBuilder)
    036        {
    037            this.proxyFactory = proxyFactory;
    038            this.defaultImplementationBuilder = defaultImplementationBuilder;
    039        }
    040
    041        public <S, F> S build(Logger logger, Class<S> serviceInterface, Class<F> filterInterface, List<F> filters)
    042        {
    043            S terminator = defaultImplementationBuilder.createDefaultImplementation(serviceInterface);
    044
    045            return build(logger, serviceInterface, filterInterface, filters, terminator);
    046        }
    047
    048        public <S, F> S build(Logger logger, Class<S> serviceInterface, Class<F> filterInterface, List<F> filters,
    049                S terminator)
    050        {
    051            if (filters.isEmpty())
    052                return terminator;
    053
    054            BridgeBuilder<S, F> bb = new BridgeBuilder<S, F>(logger, serviceInterface, filterInterface, proxyFactory);
    055
    056            // The first bridge will point to the terminator.
    057            // Like service decorators, we work deepest (last)
    058            // to shallowest (first)
    059
    060            S next = terminator;
    061            int count = filters.size();
    062
    063            for (int i = count - 1; i >= 0; i--)
    064            {
    065                F filter = filters.get(i);
    066
    067                next = bb.instantiateBridge(next, filter);
    068            }
    069
    070            return next;
    071        }
    072
    073    }