001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.client;
019
020import org.apache.hadoop.hbase.client.metrics.ScanMetrics;
021import org.apache.yetus.audience.InterfaceAudience;
022
023/**
024 * The base interface for scan result consumer.
025 */
026@InterfaceAudience.Public
027public interface ScanResultConsumerBase {
028  /**
029   * Indicate that we hit an unrecoverable error and the scan operation is terminated.
030   * <p>
031   * We will not call {@link #onComplete()} after calling {@link #onError(Throwable)}.
032   */
033  void onError(Throwable error);
034
035  /**
036   * Indicate that the scan operation is completed normally.
037   */
038  void onComplete();
039
040  /**
041   * If {@code scan.isScanMetricsEnabled()} returns true, then this method will be called prior to
042   * all other methods in this interface to give you the {@link ScanMetrics} instance for this scan
043   * operation. The {@link ScanMetrics} instance will be updated on-the-fly during the scan, you can
044   * store it somewhere to get the metrics at any time if you want.
045   */
046  default void onScanMetricsCreated(ScanMetrics scanMetrics) {
047  }
048}