package org.apache.helix.controller.stages;
   
   /*
    * 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.
   */
  
  import org.apache.helix.HelixDataAccessor;
  import org.apache.helix.HelixManager;
  import org.apache.helix.controller.pipeline.AbstractBaseStage;
  import org.apache.helix.controller.pipeline.StageException;
  import org.apache.log4j.Logger;
  
  
  public class ReadHealthDataStage extends AbstractBaseStage
  {
    private static final Logger LOG = Logger.getLogger(ReadHealthDataStage.class.getName());
    HealthDataCache _cache;
  
    public ReadHealthDataStage()
    {
      _cache = new HealthDataCache();
    }
  
    @Override
    public void process(ClusterEvent event) throws Exception
    {
      long startTime = System.currentTimeMillis();
  
      HelixManager manager = event.getAttribute("helixmanager");
      if (manager == null)
      {
        throw new StageException("HelixManager attribute value is null");
      }
      // DataAccessor dataAccessor = manager.getDataAccessor();
      HelixDataAccessor accessor = manager.getHelixDataAccessor();
      _cache.refresh(accessor);
  
      event.addAttribute("HealthDataCache", _cache);
  
      long processLatency = System.currentTimeMillis() - startTime;
      addLatencyToMonitor(event, processLatency);
    }
  }