content: /*
   * Copyright (C) 2019 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.offline;
  
  import androidx.annotation.WorkerThread;
  import java.io.IOException;
  
  /** A writable index of {@link Download Downloads}. */
  @WorkerThread
  public interface WritableDownloadIndex extends DownloadIndex {
  
    /**
     * Adds or replaces a {@link Download}.
     *
     * <p>This method may be slow and shouldn't normally be called on the main thread.
     *
     * @param download The {@link Download} to be added.
     * @throws IOException If an error occurs setting the state.
     */
    void putDownload(Download download) throws IOException;
  
    /**
     * Removes the download with the given ID. Does nothing if a download with the given ID does not
     * exist.
     *
     * <p>This method may be slow and shouldn't normally be called on the main thread.
     *
     * @param id The ID of the download to remove.
     * @throws IOException If an error occurs removing the state.
     */
    void removeDownload(String id) throws IOException;
  
    /**
     * Sets all {@link Download#STATE_DOWNLOADING} states to {@link Download#STATE_QUEUED}.
     *
     * <p>This method may be slow and shouldn't normally be called on the main thread.
     *
     * @throws IOException If an error occurs updating the state.
     */
    void setDownloadingStatesToQueued() throws IOException;
  
    /**
     * Sets all states to {@link Download#STATE_REMOVING}.
     *
     * <p>This method may be slow and shouldn't normally be called on the main thread.
     *
     * @throws IOException If an error occurs updating the state.
     */
    void setStatesToRemoving() throws IOException;
  
    /**
     * Sets the stop reason of the downloads in a terminal state ({@link Download#STATE_COMPLETED},
     * {@link Download#STATE_FAILED}).
     *
     * <p>This method may be slow and shouldn't normally be called on the main thread.
     *
     * @param stopReason The stop reason.
     * @throws IOException If an error occurs updating the state.
     */
    void setStopReason(int stopReason) throws IOException;
  
    /**
     * Sets the stop reason of the download with the given ID in a terminal state ({@link
     * Download#STATE_COMPLETED}, {@link Download#STATE_FAILED}). Does nothing if a download with the
     * given ID does not exist, or if it's not in a terminal state.
     *
     * <p>This method may be slow and shouldn't normally be called on the main thread.
     *
     * @param id The ID of the download to update.
     * @param stopReason The stop reason.
     * @throws IOException If an error occurs updating the state.
     */
    void setStopReason(String id, int stopReason) throws IOException;
  }
  