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.internal.composites;
  
  import java.nio.ByteBuffer;
  
  import org.apache.cassandra.schema.ColumnMetadata;
  import org.apache.cassandra.cql3.Operator;
  import org.apache.cassandra.db.*;
  import org.apache.cassandra.db.marshal.CollectionType;
  import org.apache.cassandra.db.marshal.SetType;
  import org.apache.cassandra.db.rows.*;
  import org.apache.cassandra.index.internal.CassandraIndex;
  import org.apache.cassandra.index.internal.IndexEntry;
  import org.apache.cassandra.schema.IndexMetadata;
  
  /**
   * Index the value of a collection cell.
   *
   * This is a lot like an index on REGULAR, except that we also need to make
   * the collection key part of the index entry so that:
   *   1) we don't have to scan the whole collection at query time to know the
   *   entry is stale and if it still satisfies the query.
   *   2) if a collection has multiple time the same value, we need one entry
   *   for each so that if we delete one of the value only we only delete the
   *   entry corresponding to that value.
   */
  public class CollectionValueIndex extends CassandraIndex
  {
      public CollectionValueIndex(ColumnFamilyStore baseCfs, IndexMetadata indexDef)
      {
          super(baseCfs, indexDef);
      }
  
      public ByteBuffer getIndexedValue(ByteBuffer partitionKey,
                                        Clustering<?> clustering,
                                        CellPath path, ByteBuffer cellValue)
      {
          return cellValue;
      }
  
      public <T> CBuilder buildIndexClusteringPrefix(ByteBuffer partitionKey,
                                                     ClusteringPrefix<T> prefix,
                                                     CellPath path)
      {
          CBuilder builder = CBuilder.create(getIndexComparator());
          builder.add(partitionKey);
          for (int i = 0; i < prefix.size(); i++)
              builder.add(prefix.get(i), prefix.accessor());
  
          // When indexing a static column, prefix will be empty but only the
          // partition key is needed at query time.
          // In the non-static case, cell will be present during indexing but
          // not when searching (CASSANDRA-7525).
          if (prefix.size() == baseCfs.metadata().clusteringColumns().size() && path != null)
              builder.add(path.get(0));
  
          return builder;
      }
  
      public IndexEntry decodeEntry(DecoratedKey indexedValue, Row indexEntry)
      {
          Clustering<?> clustering = indexEntry.clustering();
          Clustering<?> indexedEntryClustering = null;
          if (getIndexedColumn().isStatic())
              indexedEntryClustering = Clustering.STATIC_CLUSTERING;
          else
          {
              CBuilder builder = CBuilder.create(baseCfs.getComparator());
              for (int i = 0; i < baseCfs.getComparator().size(); i++)
                  builder.add(clustering, i + 1);
              indexedEntryClustering = builder.build();
          }
  
          return new IndexEntry(indexedValue,
                                  clustering,
                                  indexEntry.primaryKeyLivenessInfo().timestamp(),
                                  clustering.bufferAt(0),
                                  indexedEntryClustering);
      }
  
      public boolean supportsOperator(ColumnMetadata indexedColumn, Operator operator)
      {
          return operator == Operator.CONTAINS && !(indexedColumn.type instanceof SetType);
      }
  
      public boolean isStale(Row data, ByteBuffer indexValue, long nowInSec)
      {
          ColumnMetadata columnDef = indexedColumn;
          ComplexColumnData complexData = data.getComplexColumnData(columnDef);
          if (complexData == null)
              return true;
  
          for (Cell<?> cell : complexData)
          {
              if (cell.isLive(nowInSec) && ((CollectionType) columnDef.type).valueComparator()
                                                                            .compare(indexValue, cell.buffer()) == 0)
                  return false;
          }
          return true;
      }
  }
  