| /** |
| * 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.processor.aggregate; |
| |
| import org.apache.camel.Exchange; |
| |
| /** |
| * An {@link org.apache.camel.processor.aggregate.AggregationStrategy} which just uses the original exchange |
| * which can be needed when you want to preserve the original Exchange. For example when splitting an Exchange |
| * and then you may want to keep routing using the original Exchange. |
| * <p/> |
| * You must call {@link #setOriginal(org.apache.camel.Exchange)} before this aggregation strategy can be used, |
| * as it needs to have a reference to the original exchange. |
| * |
| * @see org.apache.camel.processor.Splitter |
| * @version $Revision$ |
| */ |
| public class UseOriginalAggregationStrategy implements AggregationStrategy { |
| |
| // must use a thread local to cater for concurrency |
| private final ThreadLocal<Exchange> original = new ThreadLocal<Exchange>(); |
| private final boolean propagateException; |
| |
| public UseOriginalAggregationStrategy(boolean propagateException) { |
| this.propagateException = propagateException; |
| } |
| |
| public void setOriginal(Exchange exchange) { |
| if (exchange == null) { |
| // clear it |
| this.original.remove(); |
| } else { |
| this.original.set(exchange); |
| } |
| } |
| |
| public Exchange aggregate(Exchange oldExchange, Exchange newExchange) { |
| Exchange answer = original.get(); |
| if (answer == null) { |
| throw new IllegalStateException("Original Exchange has not been set"); |
| } |
| |
| if (propagateException) { |
| Exception exception = checkException(oldExchange, newExchange); |
| if (exception != null) { |
| answer.setException(exception); |
| } |
| } |
| return answer; |
| } |
| |
| protected Exception checkException(Exchange oldExchange, Exchange newExchange) { |
| if (oldExchange == null) { |
| return newExchange.getException(); |
| } else { |
| return (newExchange != null && newExchange.getException() != null) |
| ? newExchange.getException() |
| : oldExchange.getException(); |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return "UseOriginalAggregationStrategy"; |
| } |
| } |