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 */
017package org.apache.camel.spi;
018
019import org.apache.camel.NamedNode;
020import org.apache.camel.Processor;
021
022/**
023 * A factory to create {@link Processor} based on the {@link org.apache.camel.model.ProcessorDefinition definition}.
024 * <p/>
025 * This allows you to implement a custom factory in which you can control the creation of the processors.
026 * It also allows you to manipulate the {@link org.apache.camel.model.ProcessorDefinition definition}s for example to
027 * configure or change options. Its also possible to add new steps in the route by adding outputs to
028 * {@link org.apache.camel.model.ProcessorDefinition definition}s.
029 * <p/>
030 * <b>Important:</b> By returning <tt>null</tt> from the create methods you fallback to let the default implementation in Camel create
031 * the {@link Processor}. You want to do this if you <i>only</i> want to manipulate the
032 * {@link org.apache.camel.model.ProcessorDefinition definition}s.
033 */
034public interface ProcessorFactory {
035
036    /**
037     * Creates the child processor.
038     * <p/>
039     * The child processor is an output from the given definition, for example the sub route in a splitter EIP.
040     *
041     * @param routeContext  the route context
042     * @param definition    the definition which represents the processor
043     * @param mandatory     whether or not the child is mandatory
044     * @return the created processor, or <tt>null</tt> to let the default implementation in Camel create the processor.
045     * @throws Exception can be thrown if error creating the processor
046     */
047    Processor createChildProcessor(RouteContext routeContext, NamedNode definition, boolean mandatory) throws Exception;
048
049    /**
050     * Creates the processor.
051     *
052     * @param routeContext  the route context
053     * @param definition    the definition which represents the processor
054     * @return the created processor, or <tt>null</tt> to let the default implementation in Camel create the processor.
055     * @throws Exception can be thrown if error creating the processor
056     */
057    Processor createProcessor(RouteContext routeContext, NamedNode definition) throws Exception;
058
059}