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.asterix.om.lazy;
  
  import java.util.Objects;
  
  import org.apache.asterix.dataflow.data.nontagged.serde.AInt32SerializerDeserializer;
  import org.apache.asterix.om.types.ATypeTag;
  import org.apache.asterix.om.types.AbstractCollectionType;
  import org.apache.asterix.om.types.IAType;
  import org.apache.hyracks.api.exceptions.HyracksDataException;
  
  /**
   * Common implementation for both {@link ATypeTag#ARRAY} and {@link ATypeTag#MULTISET}
   */
  public abstract class AbstractListLazyVisitablePointable extends AbstractLazyNestedVisitablePointable {
      private final int headerSize;
      private final AbstractLazyVisitablePointable itemVisitablePointable;
      private int numberOfItems;
      protected int currentIndex;
      protected int itemsOffset;
  
      AbstractListLazyVisitablePointable(boolean tagged, AbstractCollectionType listType) {
          super(tagged, listType.getTypeTag());
          Objects.requireNonNull(listType);
          Objects.requireNonNull(listType.getItemType());
          //1 for typeTag if tagged, 1 for itemTypeTag, 4 for length
          headerSize = (isTagged() ? 1 : 0) + 1 + 4;
          itemVisitablePointable = createVisitablePointable(listType.getItemType());
      }
  
      @Override
      public final int getNumberOfChildren() {
          return numberOfItems;
      }
  
      @Override
      final void init(byte[] data, int offset, int length) {
          int pointer = headerSize + offset;
          numberOfItems = AInt32SerializerDeserializer.getInt(data, pointer);
          itemsOffset = pointer + 4;
          currentIndex = 0;
      }
  
      @Override
      public AbstractLazyVisitablePointable getChildVisitablePointable() throws HyracksDataException {
          itemVisitablePointable.set(getChildValue());
          return itemVisitablePointable;
      }
  
      @Override
      public <R, T> R accept(ILazyVisitablePointableVisitor<R, T> visitor, T arg) throws HyracksDataException {
          return visitor.visit(this, arg);
      }
  
      abstract AbstractLazyVisitablePointable createVisitablePointable(IAType itemType);
  }
  