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;
  
  import org.apache.cassandra.db.filter.ClusteringIndexFilter;
  import org.apache.cassandra.db.filter.ColumnFilter;
  import org.apache.cassandra.db.partitions.PartitionUpdate;
  import org.apache.cassandra.db.rows.UnfilteredRowIterator;
  import org.apache.cassandra.db.rows.UnfilteredRowIteratorWithLowerBound;
  import org.apache.cassandra.io.sstable.SSTableReadsListener;
  import org.apache.cassandra.io.sstable.format.SSTableReader;
  import org.apache.cassandra.schema.TableId;
  import org.apache.cassandra.utils.FBUtilities;
  
  import static org.apache.cassandra.config.CassandraRelevantProperties.STORAGE_HOOK;
  
  public interface StorageHook
  {
      public static final StorageHook instance = createHook();
  
      public void reportWrite(TableId tableId, PartitionUpdate partitionUpdate);
      public void reportRead(TableId tableId, DecoratedKey key);
      public UnfilteredRowIteratorWithLowerBound makeRowIteratorWithLowerBound(ColumnFamilyStore cfs,
                                                                               SSTableReader sstable,
                                                                               DecoratedKey partitionKey,
                                                                               ClusteringIndexFilter filter,
                                                                               ColumnFilter selectedColumns,
                                                                               SSTableReadsListener listener);
      public UnfilteredRowIterator makeRowIterator(ColumnFamilyStore cfs,
                                                   SSTableReader sstable,
                                                   DecoratedKey key,
                                                   Slices slices,
                                                   ColumnFilter selectedColumns,
                                                   boolean reversed,
                                                   SSTableReadsListener listener);
  
      static StorageHook createHook()
      {
          String className = STORAGE_HOOK.getString();
          if (className != null)
          {
              return FBUtilities.construct(className, StorageHook.class.getSimpleName());
          }
  
          return new StorageHook()
          {
              public void reportWrite(TableId tableId, PartitionUpdate partitionUpdate) {}
  
              public void reportRead(TableId tableId, DecoratedKey key) {}
  
              public UnfilteredRowIteratorWithLowerBound makeRowIteratorWithLowerBound(ColumnFamilyStore cfs,
                                                                                       SSTableReader sstable, DecoratedKey partitionKey,
                                                                                       ClusteringIndexFilter filter,
                                                                                       ColumnFilter selectedColumns,
                                                                                       SSTableReadsListener listener)
              {
                  return new UnfilteredRowIteratorWithLowerBound(partitionKey,
                                                                 sstable,
                                                                 filter,
                                                                 selectedColumns,
                                                                 listener);
              }
  
              public UnfilteredRowIterator makeRowIterator(ColumnFamilyStore cfs,
                                                           SSTableReader sstable,
                                                           DecoratedKey key,
                                                           Slices slices,
                                                           ColumnFilter selectedColumns,
                                                           boolean reversed,
                                                           SSTableReadsListener listener)
              {
                  return sstable.rowIterator(key, slices, selectedColumns, reversed, listener);
              }
          };
      }
  }