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.index.sai.memory;
  
  import org.apache.cassandra.db.Clustering;
  import org.apache.cassandra.db.DecoratedKey;
  import org.apache.cassandra.db.PartitionPosition;
  import org.apache.cassandra.dht.AbstractBounds;
  import org.apache.cassandra.index.sai.QueryContext;
  import org.apache.cassandra.index.sai.StorageAttachedIndex;
  import org.apache.cassandra.index.sai.disk.format.IndexDescriptor;
  import org.apache.cassandra.index.sai.utils.IndexIdentifier;
  import org.apache.cassandra.index.sai.disk.v1.segment.SegmentMetadata;
  import org.apache.cassandra.index.sai.iterators.KeyRangeIterator;
  import org.apache.cassandra.index.sai.plan.Expression;
  import org.apache.cassandra.index.sai.utils.PrimaryKey;
  import org.apache.cassandra.index.sai.utils.PrimaryKeys;
  import org.apache.cassandra.utils.Pair;
  import org.apache.cassandra.utils.bytecomparable.ByteComparable;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.util.Iterator;
  import java.util.function.Function;
  
  public abstract class MemoryIndex implements MemtableOrdering
  {
      protected final StorageAttachedIndex index;
  
      protected MemoryIndex(StorageAttachedIndex index)
      {
          this.index = index;
      }
  
      public abstract long add(DecoratedKey key, Clustering<?> clustering, ByteBuffer value);
  
      public abstract long update(DecoratedKey key, Clustering<?> clustering, ByteBuffer oldValue, ByteBuffer newValue);
  
      public abstract KeyRangeIterator search(QueryContext queryContext, Expression expression, AbstractBounds<PartitionPosition> keyRange);
  
      public abstract boolean isEmpty();
  
      public abstract ByteBuffer getMinTerm();
  
      public abstract ByteBuffer getMaxTerm();
  
      /**
       * Iterate all Term->PrimaryKeys mappings in sorted order
       */
      public abstract Iterator<Pair<ByteComparable, PrimaryKeys>> iterator();
  
      public abstract SegmentMetadata.ComponentMetadataMap writeDirect(IndexDescriptor indexDescriptor,
                                                                       IndexIdentifier indexIdentifier,
                                                                       Function<PrimaryKey, Integer> postingTransformer) throws IOException;
  }
  