/*
 * Copyright 2008 the original author or authors.
 *
 * Licensed 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.openehealth.ipf.platform.camel.flow.closure;

import groovy.lang.Closure;
import groovy.transform.stc.ClosureParams;
import groovy.transform.stc.SimpleType;
import org.apache.camel.Exchange;
import org.apache.camel.processor.aggregate.AggregationStrategy;

/**
 * An aggregation strategy that delegates to a {@link Closure}.
 *
 * @author Martin Krasser
 *
 */
public class DelegatingAggregationStrategy extends ClosureAdapter implements AggregationStrategy {

    public DelegatingAggregationStrategy(@ClosureParams(value = SimpleType.class, options = { "org.apache.camel.Exchange", "org.apache.camel.Exchange"})
                                                 Closure closure) {
        super(closure);
    }

    @Override
    public Exchange aggregate(Exchange oldExchange, Exchange newExchange) {
        Object result = call(oldExchange, newExchange);
        if (result instanceof Exchange) {
            return (Exchange)result;
        } else {
            return oldExchange;
        }
    }

}