/*
 * 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.tsfile.external.commons.collections4.iterators;

import org.apache.tsfile.external.commons.collections4.OrderedMapIterator;
import org.apache.tsfile.external.commons.collections4.ResettableIterator;

/**
 * Provides an implementation of an empty ordered map iterator.
 *
 * @param <K> the type of keys
 * @param <V> the type of mapped values
 * @since 3.1
 */
public class EmptyOrderedMapIterator<K, V> extends AbstractEmptyMapIterator<K, V>
    implements OrderedMapIterator<K, V>, ResettableIterator<K> {

  /**
   * Singleton instance of the iterator.
   *
   * @since 3.1
   */
  @SuppressWarnings("rawtypes")
  public static final OrderedMapIterator INSTANCE = new EmptyOrderedMapIterator<>();

  /**
   * Get a typed instance of the iterator.
   *
   * @param <K> the key type
   * @param <V> the value type
   * @return {@link OrderedMapIterator}&lt;K, V&gt;
   */
  public static <K, V> OrderedMapIterator<K, V> emptyOrderedMapIterator() {
    return INSTANCE;
  }

  /** Constructor. */
  protected EmptyOrderedMapIterator() {
    super();
  }
}
