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/*
 * Copyright © 2020 Cask Data, Inc.
 *
 * 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 io.cdap.delta.api;

/**
 * Reads change events.
 */
public interface EventReader {

  /**
   * Start reading events from the given offset.
   */
  void start(Offset offset);

  /**
   * Stop reading events.
   *
   * @throws InterruptedException if the reader was interrupted while stopping
   */
  default void stop() throws InterruptedException {
    stop(new StopContext() {
      @Override
      public Origin getOrigin() {
        return Origin.UNKNOWN;
      }
    });
  }

  /**
   * Stop reading events.
   * @param context the context of the stop request
   * @throws InterruptedException if the reader was interrupted while stopping
   */
  default void stop(StopContext context) throws InterruptedException {
    // no-op
  }

}