| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.camel.component.iec60870; |
| |
| import java.util.Set; |
| import java.util.concurrent.CopyOnWriteArraySet; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| public abstract class AbstractConnectionMultiplexor { |
| |
| private static final Logger LOG = LoggerFactory.getLogger(AbstractConnectionMultiplexor.class); |
| |
| public interface Handle { |
| void unregister() throws Exception; |
| } |
| |
| private final class HandleImplementation implements Handle { |
| @Override |
| public void unregister() throws Exception { |
| AbstractConnectionMultiplexor.this.unregister(this); |
| } |
| } |
| |
| private final Set<HandleImplementation> handles = new CopyOnWriteArraySet<>(); |
| |
| public synchronized Handle register() throws Exception { |
| final HandleImplementation handle = new HandleImplementation(); |
| |
| final boolean needStart = this.handles.isEmpty(); |
| this.handles.add(handle); |
| |
| if (needStart) { |
| LOG.info("Calling performStart()"); |
| performStart(); |
| } |
| |
| return handle; |
| } |
| |
| private synchronized void unregister(final HandleImplementation handle) throws Exception { |
| if (!this.handles.remove(handle)) { |
| return; |
| } |
| |
| if (this.handles.isEmpty()) { |
| LOG.info("Calling performStop()"); |
| performStop(); |
| } |
| } |
| |
| public synchronized void dispose() { |
| |
| LOG.info("Disposing"); |
| if (this.handles.isEmpty()) { |
| LOG.debug("Disposing - not started"); |
| return; |
| } |
| |
| LOG.debug("Disposing - calling performStop()"); |
| |
| this.handles.clear(); |
| try { |
| performStop(); |
| } catch (final Exception e) { |
| throw new RuntimeException("Failed to stop on dispose", e); |
| } |
| } |
| |
| protected abstract void performStart() throws Exception; |
| |
| protected abstract void performStop() throws Exception; |
| } |