/**
    * 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 org.apache.hadoop.hbase.client;
  
  import static org.apache.hadoop.hbase.client.ConnectionUtils.createClosestRowAfter;
  import static org.apache.hadoop.hbase.client.ConnectionUtils.isEmptyStartRow;
  import static org.apache.hadoop.hbase.client.ConnectionUtils.noMoreResultsForScan;
  
  import java.io.IOException;
  import java.util.concurrent.ExecutorService;
  
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.ipc.RpcControllerFactory;
  
  /**
   * ClientSimpleScanner implements a sync scanner behaviour. The cache is a simple list. The prefetch
   * is invoked only when the application finished processing the entire cache.
   */
  @InterfaceAudience.Private
  public class ClientSimpleScanner extends ClientScanner {
    public ClientSimpleScanner(Configuration configuration, Scan scan, TableName name,
        ClusterConnection connection, RpcRetryingCallerFactory rpcCallerFactory,
        RpcControllerFactory rpcControllerFactory, ExecutorService pool,
        int replicaCallTimeoutMicroSecondScan) throws IOException {
      super(configuration, scan, name, connection, rpcCallerFactory, rpcControllerFactory, pool,
          replicaCallTimeoutMicroSecondScan);
    }
  
    @Override
    protected boolean setNewStartKey() {
      if (noMoreResultsForScan(scan, currentRegion)) {
        return false;
      }
      scan.withStartRow(currentRegion.getEndKey(), true);
      return true;
    }
  
    @Override
    protected ScannerCallable createScannerCallable() {
      if (!scan.includeStartRow() && !isEmptyStartRow(scan.getStartRow())) {
        // we have not implemented locate to next row for sync client yet, so here we change the
        // inclusive of start row to true.
        scan.withStartRow(createClosestRowAfter(scan.getStartRow()), true);
      }
      return new ScannerCallable(getConnection(), getTable(), scan, this.scanMetrics,
          this.rpcControllerFactory);
    }
  }