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.arrow.vector.util;
  
  import java.util.Iterator;
  import org.apache.arrow.memory.util.ArrowBufPointer;
  import org.apache.arrow.memory.util.hash.ArrowBufHasher;
  import org.apache.arrow.memory.util.hash.SimpleHasher;
  import org.apache.arrow.vector.ElementAddressableVector;
  
  /**
   * Iterator for traversing elements of a {@link ElementAddressableVector}.
   *
   * @param <T> vector type.
   */
  public class ElementAddressableVectorIterator<T extends ElementAddressableVector>
      implements Iterator<ArrowBufPointer> {
  
    private final T vector;
  
    /** Index of the next element to access. */
    private int index = 0;
  
    private final ArrowBufPointer reusablePointer;
  
    /**
     * Constructs an iterator for the {@link ElementAddressableVector}.
     *
     * @param vector the vector to iterate.
     */
    public ElementAddressableVectorIterator(T vector) {
      this(vector, SimpleHasher.INSTANCE);
    }
  
    /**
     * Constructs an iterator for the {@link ElementAddressableVector}.
     *
     * @param vector the vector to iterate.
     * @param hasher the hasher to calculate the hash code.
     */
    public ElementAddressableVectorIterator(T vector, ArrowBufHasher hasher) {
      this.vector = vector;
      reusablePointer = new ArrowBufPointer(hasher);
    }
  
    @Override
    public boolean hasNext() {
      return index < vector.getValueCount();
    }
  
    /**
     * Retrieves the next pointer from the vector.
     *
     * @return the pointer pointing to the next element in the vector. Note that the returned pointer
     *     is only valid before the next call to this method.
     */
    @Override
    public ArrowBufPointer next() {
      vector.getDataPointer(index, reusablePointer);
      index += 1;
      return reusablePointer;
    }
  
    /**
     * Retrieves the next pointer from the vector.
     *
     * @param outPointer the pointer to populate.
     */
    public void next(ArrowBufPointer outPointer) {
      vector.getDataPointer(index, outPointer);
      index += 1;
    }
  }
  