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.management;
018    
019    import java.util.Map;
020    
021    import org.apache.camel.Processor;
022    import org.apache.camel.model.ProcessorDefinition;
023    import org.apache.camel.spi.InterceptStrategy;
024    
025    /**
026     * This strategy class wraps targeted processors with a
027     * {@link InstrumentationProcessor}. Each InstrumentationProcessor has an
028     * embedded {@link PerformanceCounter} for monitoring performance metrics.
029     * <p/>
030     * This class looks up a map to determine which PerformanceCounter should go into the
031     * InstrumentationProcessor for any particular target processor.
032     *
033     * @version $Revision: 771041 $
034     */
035    public class InstrumentationInterceptStrategy implements InterceptStrategy {
036    
037        private Map<ProcessorDefinition, PerformanceCounter> registeredCounters;
038    
039        public InstrumentationInterceptStrategy(Map<ProcessorDefinition, PerformanceCounter> registeredCounters) {
040            this.registeredCounters = registeredCounters;
041        }
042    
043        public Processor wrapProcessorInInterceptors(ProcessorDefinition processorDefinition, Processor target, Processor nextTarget) throws Exception {
044            // dont double wrap it
045            if (target instanceof InstrumentationProcessor) {
046                return target;
047            }
048    
049            // only wrap a performance counter if we have it registered in JMX by the jmx agent
050            PerformanceCounter counter = registeredCounters.get(processorDefinition);
051            if (counter != null) {
052                InstrumentationProcessor wrapper = new InstrumentationProcessor(counter);
053                wrapper.setProcessor(target);
054                wrapper.setType(processorDefinition.getShortName());
055                // remove to not double wrap it
056                registeredCounters.remove(processorDefinition);
057                return wrapper;
058            }
059    
060            return target;
061        }
062    
063        @Override
064        public String toString() {
065            return "Instrument";
066        }
067    }