/**
    * 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.hbase.io.hfile;
  
  import org.codehaus.jackson.annotate.JsonIgnoreProperties;
  
  import com.yammer.metrics.core.Histogram;
  import com.yammer.metrics.stats.Snapshot;
  
  /**
   * Snapshot of block cache age in cache.
   * This object is preferred because we can control how it is serialized out when JSON'ing.
   */
  @JsonIgnoreProperties({"ageHistogram", "snapshot"})
  public class AgeSnapshot {
    private final Histogram ageHistogram;
    private final Snapshot snapshot;
  
    AgeSnapshot(final Histogram ageHistogram) {
      this.ageHistogram = ageHistogram;
      this.snapshot = ageHistogram.getSnapshot();
    }
  
    public double get75thPercentile() {
      return snapshot.get75thPercentile();
    }
  
    public double get95thPercentile() {
      return snapshot.get95thPercentile();
    }
  
    public double get98thPercentile() {
      return snapshot.get98thPercentile();
    }
  
    public double get999thPercentile() {
      return snapshot.get999thPercentile();
    }
  
    public double get99thPercentile() {
      return snapshot.get99thPercentile();
    }
  
    public double getMean() {
      return this.ageHistogram.mean();
    }
  
    public double getMax() {
      return ageHistogram.max();
    }
  
    public double getMin() {
      return ageHistogram.min();
    }
  
    public double getStdDev() {
      return ageHistogram.stdDev();
    }
  }