/*
 * 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.hadoop.registry.server.services;

import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.api.BackgroundCallback;
import org.apache.curator.framework.api.CuratorEvent;
import org.apache.hadoop.registry.server.integration.RMRegistryOperationsService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.concurrent.atomic.AtomicInteger;

/**
 * Curator callback for delete operations completing.
 * <p>
 * This callback logs at debug and increments the event counter.
 */
public class DeleteCompletionCallback implements BackgroundCallback {
  private static final Logger LOG =
      LoggerFactory.getLogger(RMRegistryOperationsService.class);

  private AtomicInteger events = new AtomicInteger(0);

  @Override
  public void processResult(CuratorFramework client,
      CuratorEvent event) throws
      Exception {
    if (LOG.isDebugEnabled()) {
      LOG.debug("Delete event {}", event);
    }
    events.incrementAndGet();
  }

  /**
   * Get the number of deletion events
   * @return the count of events
   */
  public int getEventCount() {
    return events.get();
  }
}