content: /*
   * 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.component.metrics;
  
  import com.codahale.metrics.MetricRegistry;
  import com.codahale.metrics.Timer;
  import org.apache.camel.Exchange;
  import org.apache.camel.Message;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import static org.apache.camel.component.metrics.MetricsConstants.HEADER_TIMER_ACTION;
  
  public class TimerProducer extends AbstractMetricsProducer {
  
      private static final Logger LOG = LoggerFactory.getLogger(TimerProducer.class);
  
      public TimerProducer(MetricsEndpoint endpoint) {
          super(endpoint);
      }
  
      @Override
      protected void doProcess(Exchange exchange, MetricsEndpoint endpoint, MetricRegistry registry, String metricsName)
              throws Exception {
          Message in = exchange.getIn();
          MetricsTimerAction action = endpoint.getAction();
          MetricsTimerAction finalAction = in.getHeader(HEADER_TIMER_ACTION, action, MetricsTimerAction.class);
          if (finalAction == MetricsTimerAction.start) {
              handleStart(exchange, registry, metricsName);
          } else if (finalAction == MetricsTimerAction.stop) {
              handleStop(exchange, metricsName);
          } else {
              LOG.warn("No action provided for timer \"{}\"", metricsName);
          }
      }
  
      void handleStart(Exchange exchange, MetricRegistry registry, String metricsName) {
          String propertyName = getPropertyName(metricsName);
          Timer.Context context = getTimerContextFromExchange(exchange, propertyName);
          if (context == null) {
              Timer timer = registry.timer(metricsName);
              context = timer.time();
              exchange.setProperty(propertyName, context);
          } else {
              LOG.warn("Timer \"{}\" already running", metricsName);
          }
      }
  
      void handleStop(Exchange exchange, String metricsName) {
          String propertyName = getPropertyName(metricsName);
          Timer.Context context = getTimerContextFromExchange(exchange, propertyName);
          if (context != null) {
              context.stop();
              exchange.removeProperty(propertyName);
          } else {
              LOG.warn("Timer \"{}\" not found", metricsName);
          }
      }
  
      String getPropertyName(String metricsName) {
          return new StringBuilder("timer")
                  .append(":")
                  .append(metricsName)
                  .toString();
      }
  
      Timer.Context getTimerContextFromExchange(Exchange exchange, String propertyName) {
          return exchange.getProperty(propertyName, Timer.Context.class);
      }
  }
  