content: /**
   * Copyright The Apache Software Foundation
   *
   * 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 com.alibaba.wasp.metrics.lib;
  
  /**
   * Metrics Histogram interface. Implementing classes will expose computed
   * quartile values through the metrics system.
   */
  public interface MetricHistogram {
  
    // Strings used to create metrics names.
    static final String NUM_OPS_METRIC_NAME = "_num_ops";
    static final String MIN_METRIC_NAME = "_min";
    static final String MAX_METRIC_NAME = "_max";
    static final String MEAN_METRIC_NAME = "_mean";
    static final String MEDIAN_METRIC_NAME = "_median";
    static final String SEVENTY_FIFTH_PERCENTILE_METRIC_NAME = "_75th_percentile";
    static final String NINETY_FIFTH_PERCENTILE_METRIC_NAME = "_95th_percentile";
    static final String NINETY_NINETH_PERCENTILE_METRIC_NAME = "_99th_percentile";
  
    /**
     * Add a single value to a histogram's stream of values.
     * @param value
     */
    void add(long value);
  
  }
  