Java tutorial
/** * 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.util; import java.util.ArrayList; import java.util.Collections; import java.util.List; import org.apache.camel.Exchange; import org.apache.camel.spi.Synchronization; import org.apache.commons.logging.Log; /** * @version $Revision$ */ public final class UnitOfWorkHelper { private UnitOfWorkHelper() { } @SuppressWarnings("unchecked") public static void doneSynchronizations(Exchange exchange, List<Synchronization> synchronizations, Log log) { boolean failed = exchange.isFailed(); if (synchronizations != null && !synchronizations.isEmpty()) { // work on a copy of the list to avoid any modification which may cause ConcurrentModificationException List<Synchronization> copy = new ArrayList<Synchronization>(synchronizations); // reverse so we invoke it FILO style instead of FIFO Collections.reverse(copy); // and honor if any was ordered by sorting it accordingly Collections.sort(copy, new OrderedComparator()); // invoke synchronization callbacks for (Synchronization synchronization : copy) { try { if (failed) { if (log.isTraceEnabled()) { log.trace( "Invoking synchronization.onFailure: " + synchronization + " with " + exchange); } synchronization.onFailure(exchange); } else { if (log.isTraceEnabled()) { log.trace("Invoking synchronization.onComplete: " + synchronization + " with " + exchange); } synchronization.onComplete(exchange); } } catch (Throwable e) { // must catch exceptions to ensure all synchronizations have a chance to run log.warn("Exception occurred during onCompletion. This exception will be ignored.", e); } } } } }