/*
 * 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.regionserver;

import java.io.IOException;
import java.util.Optional;
import org.apache.hadoop.hbase.coprocessor.ObserverContext;
import org.apache.hadoop.hbase.coprocessor.RegionCoprocessor;
import org.apache.hadoop.hbase.coprocessor.RegionCoprocessorEnvironment;
import org.apache.hadoop.hbase.coprocessor.RegionObserver;
import org.apache.hadoop.hbase.regionserver.compactions.CompactionLifeCycleTracker;
import org.apache.hadoop.hbase.regionserver.compactions.CompactionRequest;

/**
 * RegionObserver that just reimplements the default behavior, in order to validate that all the
 * necessary APIs for this are public This observer is also used in
 * {@code TestFromClientSideWithCoprocessor} and {@link TestCompactionWithCoprocessor} to make sure
 * that a wide range of functionality still behaves as expected.
 */
public class NoOpScanPolicyObserver implements RegionCoprocessor, RegionObserver {

  @Override
  public Optional<RegionObserver> getRegionObserver() {
    return Optional.of(this);
  }

  @Override
  public InternalScanner preFlush(ObserverContext<RegionCoprocessorEnvironment> c, Store store,
    InternalScanner scanner, FlushLifeCycleTracker tracker) throws IOException {
    return new DelegatingInternalScanner(scanner);
  }

  @Override
  public InternalScanner preCompact(ObserverContext<RegionCoprocessorEnvironment> c, Store store,
    InternalScanner scanner, ScanType scanType, CompactionLifeCycleTracker tracker,
    CompactionRequest request) throws IOException {
    return new DelegatingInternalScanner(scanner);
  }

  // TODO add for postScannerOpen
}
