    001    // Copyright 2007 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.Registry;
    018    import org.apache.tapestry5.ioc.internal.util.OneShotLock;
    019    import org.slf4j.Logger;
    020
    021    import java.util.List;
    022
    023    /**
    024     * Startup service for Tapestry IoC: automatically invoked at {@linkplain Registry#performRegistryStartup() registry
    025     * startup} to execute a series of operations, via its ordered configuration of Runnable objects.
    026     */
    027    public class RegistryStartup implements Runnable
    028    {
    029        private final Logger logger;
    030
    031        private final List<Runnable> configuration;
    032
    033        private final OneShotLock lock = new OneShotLock();
    034
    035        public RegistryStartup(Logger logger, final List<Runnable> configuration)
    036        {
    037            this.logger = logger;
    038            this.configuration = configuration;
    039        }
    040
    041        /**
    042         * Invokes run() on each contributed object. If the object throws a runtime exception, it is logged but startup
    043         * continues anyway. This method may only be {@linkplain OneShotLock invoked once}.
    044         */
    045        public void run()
    046        {
    047            lock.lock();
    048
    049            // Do we want extra exception catching here?
    050
    051            for (Runnable r : configuration)
    052            {
    053                try
    054                {
    055                    r.run();
    056                }
    057                catch (RuntimeException ex)
    058                {
    059                    logger.error(ServiceMessages.startupFailure(ex));
    060                }
    061            }
    062
    063            // We don't need them any more since this method can only be run once. It's a insignificant
    064            // savings, but still a nice thing to do.
    065
    066            configuration.clear();
    067        }
    068
    069    }