001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.camel.util;
018    
019    import java.util.List;
020    
021    import org.apache.camel.model.ChoiceType;
022    import org.apache.camel.model.ProcessorType;
023    import org.apache.camel.model.WhenType;
024    
025    /**
026     * Helper class for ProcessorType and the other model classes.
027     */
028    public final class ProcessorTypeHelper {
029    
030        private ProcessorTypeHelper() {
031        }
032    
033        /**
034         * Looks for the given type in the list of outputs and recurring all the children as well.
035         * Will stop at first found and return it.
036         *
037         * @param outputs  list of outputs, can be null or empty.
038         * @param type     the type to look for
039         * @return         the first found type, or <tt>null</tt> if not found
040         */
041        @SuppressWarnings("unchecked")
042        public static <T> T findFirstTypeInOutputs(List<ProcessorType<?>> outputs, Class<T> type) {
043            if (outputs == null || outputs.isEmpty()) {
044                return null;
045            }
046    
047            for (ProcessorType out : outputs) {
048                if (type.isInstance(out)) {
049                    return type.cast(out);
050                }
051    
052                // special for choice
053                if (out instanceof ChoiceType) {
054                    ChoiceType choice = (ChoiceType) out;
055                    for (WhenType when : choice.getWhenClauses()) {
056                        List<ProcessorType<?>> children = when.getOutputs();
057                        T child = findFirstTypeInOutputs(children, type);
058                        if (child != null) {
059                            return child;
060                        }
061                    }
062    
063                    List<ProcessorType<?>> children = choice.getOtherwise().getOutputs();
064                    T child = findFirstTypeInOutputs(children, type);
065                    if (child != null) {
066                        return child;
067                    }
068                }
069    
070                // try children as well
071                List<ProcessorType<?>> children = out.getOutputs();
072                T child = findFirstTypeInOutputs(children, type);
073                if (child != null) {
074                    return child;
075                }
076            }
077    
078            return null;
079        }
080    
081    }