/**
    * 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 java.io.IOException;
  
  import org.apache.hadoop.hbase.HRegionInfo;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.ipc.PayloadCarryingRpcController;
  import org.apache.hadoop.hbase.ipc.RpcControllerFactory;
  import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
  import org.apache.hadoop.hbase.protobuf.RequestConverter;
  import org.apache.hadoop.hbase.protobuf.generated.AdminProtos.FlushRegionRequest;
  import org.apache.hadoop.hbase.protobuf.generated.AdminProtos.FlushRegionResponse;
  import org.apache.hadoop.hbase.util.Bytes;
  import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
  import org.mortbay.log.Log;
  
  import com.google.protobuf.ServiceException;
  
  /**
   * A Callable for flushRegion() RPC.
   */
  @InterfaceAudience.Private
  public class FlushRegionCallable extends RegionAdminServiceCallable<FlushRegionResponse> {
  
    private final byte[] regionName;
    private final boolean writeFlushWalMarker;
    private boolean reload;
  
    public FlushRegionCallable(ClusterConnection connection,
        RpcControllerFactory rpcControllerFactory, TableName tableName, byte[] regionName,
        byte[] regionStartKey, boolean writeFlushWalMarker) {
      super(connection, rpcControllerFactory, tableName, regionStartKey);
      this.regionName = regionName;
      this.writeFlushWalMarker = writeFlushWalMarker;
    }
  
    public FlushRegionCallable(ClusterConnection connection,
        RpcControllerFactory rpcControllerFactory, HRegionInfo regionInfo,
        boolean writeFlushWalMarker) {
      this(connection, rpcControllerFactory, regionInfo.getTable(), regionInfo.getRegionName(),
        regionInfo.getStartKey(), writeFlushWalMarker);
    }
  
    @Override
    public FlushRegionResponse call(int callTimeout) throws Exception {
      return flushRegion();
    }
  
    @Override
    public void prepare(boolean reload) throws IOException {
      super.prepare(reload);
      this.reload = reload;
    }
  
    private FlushRegionResponse flushRegion() throws IOException {
      // check whether we should still do the flush to this region. If the regions are changed due
      // to splits or merges, etc return success
      if (!Bytes.equals(location.getRegionInfo().getRegionName(), regionName)) {
        if (!reload) {
          throw new IOException("Cached location seems to be different than requested region.");
        }
        Log.info("Skipping flush region, because the located region "
            + Bytes.toStringBinary(location.getRegionInfo().getRegionName()) + " is different than "
            + " requested region " + Bytes.toStringBinary(regionName));
        return FlushRegionResponse.newBuilder()
            .setLastFlushTime(EnvironmentEdgeManager.currentTime())
            .setFlushed(false)
            .setWroteFlushWalMarker(false)
            .build();
      }
  
      FlushRegionRequest request =
          RequestConverter.buildFlushRegionRequest(regionName, writeFlushWalMarker);
  
      try {
        PayloadCarryingRpcController controller = rpcControllerFactory.newController();
        controller.setPriority(tableName);
        return stub.flushRegion(controller, request);
      } catch (ServiceException se) {
        throw ProtobufUtil.getRemoteException(se);
     }
   }
 }