content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.master.service.metrics;
  
  /**
   * Created by {@link MetricsService.Factory}.
   * This service differs from {@link AlwaysOnMetricsService} because it reports metrics after
   * being promoted and stops reporting metrics after being demoted or stopped.
   */
  class PrimaryOnlyMetricsService extends MetricsService {
    @Override
    public void start() {
      LOG.info("Starting {}", this.getClass().getSimpleName());
    }
  
    @Override
    public void promote() {
      LOG.info("Promoting {}", this.getClass().getSimpleName());
      startMetricsSystem();
    }
  
    @Override
    public void demote() {
      LOG.info("Demoting {}", this.getClass().getSimpleName());
      stopMetricsSystem();
    }
  
    @Override
    public void stop() {
      LOG.info("Stopping {}", this.getClass().getSimpleName());
      stopMetricsSystem();
    }
  }
  