content: /*
   * 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.cassandra.db.commitlog;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.nio.channels.FileChannel;
  import java.nio.file.Path;
  
  import net.openhft.chronicle.core.util.ThrowingFunction;
  import org.apache.cassandra.io.FSWriteError;
  import org.apache.cassandra.utils.SyncUtil;
  
  /**
   * Writes to the backing commit log file only on sync, allowing transformations of the mutations,
   * such as compression or encryption, before writing out to disk.
   */
  public abstract class FileDirectSegment extends CommitLogSegment
  {
      volatile long lastWrittenPos = 0;
  
      FileDirectSegment(AbstractCommitLogSegmentManager manager, ThrowingFunction<Path, FileChannel, IOException> channelFactory)
      {
          super(manager, channelFactory);
      }
  
      @Override
      void writeLogHeader()
      {
          super.writeLogHeader();
          try
          {
              channel.write((ByteBuffer) buffer.duplicate().flip());
              manager.addSize(lastWrittenPos = buffer.position());
          }
          catch (IOException e)
          {
              throw new FSWriteError(e, getPath());
          }
      }
  
      @Override
      protected void internalClose()
      {
          try
          {
              manager.getBufferPool().releaseBuffer(buffer);
              super.internalClose();
          }
          finally
          {
              manager.notifyBufferFreed();
          }
      }
  
      @Override
      protected void flush(int startMarker, int nextMarker)
      {
          try
          {
              SyncUtil.force(channel, true);
          }
          catch (Exception e)
          {
              throw new FSWriteError(e, getPath());
          }
      }
  }
  