001package ca.uhn.fhir.jpa.subscription.channel.subscription;
002
003/*-
004 * #%L
005 * HAPI FHIR Storage api
006 * %%
007 * Copyright (C) 2014 - 2022 Smile CDR, Inc.
008 * %%
009 * Licensed under the Apache License, Version 2.0 (the "License");
010 * you may not use this file except in compliance with the License.
011 * You may obtain a copy of the License at
012 *
013 *      http://www.apache.org/licenses/LICENSE-2.0
014 *
015 * Unless required by applicable law or agreed to in writing, software
016 * distributed under the License is distributed on an "AS IS" BASIS,
017 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
018 * See the License for the specific language governing permissions and
019 * limitations under the License.
020 * #L%
021 */
022
023import ca.uhn.fhir.jpa.subscription.channel.api.IChannelReceiver;
024import org.apache.commons.lang3.Validate;
025import org.springframework.messaging.Message;
026import org.springframework.messaging.MessageHandler;
027import org.springframework.messaging.SubscribableChannel;
028import org.springframework.messaging.support.AbstractSubscribableChannel;
029import org.springframework.messaging.support.ChannelInterceptor;
030
031import java.util.Set;
032
033public class BroadcastingSubscribableChannelWrapper extends AbstractSubscribableChannel implements IChannelReceiver {
034
035        private final IChannelReceiver myWrappedChannel;
036        private final MessageHandler myHandler;
037
038        public BroadcastingSubscribableChannelWrapper(IChannelReceiver theChannel) {
039                myHandler = message -> send(message);
040                theChannel.subscribe(myHandler);
041                myWrappedChannel = theChannel;
042        }
043
044        public SubscribableChannel getWrappedChannel() {
045                return myWrappedChannel;
046        }
047
048        @Override
049        protected boolean sendInternal(Message<?> theMessage, long timeout) {
050                Set<MessageHandler> subscribers = getSubscribers();
051                Validate.isTrue(subscribers.size() > 0, "Channel has zero subscribers");
052                for (MessageHandler next : subscribers) {
053                        next.handleMessage(theMessage);
054                }
055                return true;
056        }
057
058        @Override
059        public void destroy() throws Exception {
060                myWrappedChannel.destroy();
061                myWrappedChannel.unsubscribe(myHandler);
062        }
063
064        @Override
065        public void addInterceptor(ChannelInterceptor interceptor) {
066                super.addInterceptor(interceptor);
067                myWrappedChannel.addInterceptor(interceptor);
068        }
069
070        @Override
071        public String getName() {
072                return myWrappedChannel.getName();
073        }
074}