content: /*
   * Copyright (C) 2016 The Android Open Source Project
   *
   * Licensed 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.google.android.exoplayer2.upstream;
  
  /**
   * Provides estimates of the currently available bandwidth.
   */
  public interface BandwidthMeter {
  
    /**
     * A listener of {@link BandwidthMeter} events.
     */
    interface EventListener {
  
      /**
       * Called periodically to indicate that bytes have been transferred.
       * <p>
       * Note: The estimated bitrate is typically derived from more information than just
       * {@code bytes} and {@code elapsedMs}.
       *
       * @param elapsedMs The time taken to transfer the bytes, in milliseconds.
       * @param bytes The number of bytes transferred.
       * @param bitrate The estimated bitrate in bits/sec, or {@link #NO_ESTIMATE} if an estimate is
       *     not available.
       */
      void onBandwidthSample(int elapsedMs, long bytes, long bitrate);
  
    }
  
    /**
     * Indicates no bandwidth estimate is available.
     */
    long NO_ESTIMATE = -1;
  
    /**
     * Returns the estimated bandwidth in bits/sec, or {@link #NO_ESTIMATE} if an estimate is not
     * available.
     */
    long getBitrateEstimate();
  
  }
  