    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.collections4.iterators;
    018
    019import org.apache.commons.collections4.MapIterator;
    020import org.apache.commons.collections4.ResettableIterator;
    021
    022/**
    023 * Provides an implementation of an empty map iterator.
    024 *
    025 * @param <K> the type of keys
    026 * @param <V> the type of mapped values
    027 * @since 3.1
    028 */
    029public class EmptyMapIterator<K, V> extends AbstractEmptyMapIterator<K, V> implements
    030        MapIterator<K, V>, ResettableIterator<K> {
    031
    032    /**
    033     * Singleton instance of the iterator.
    034     * @since 3.1
    035     */
    036    @SuppressWarnings("rawtypes")
    037    public static final MapIterator INSTANCE = new EmptyMapIterator<>();
    038
    039    /**
    040     * Gets a typed instance of the iterator.
    041     * @param <K> the key type
    042     * @param <V> the value type
    043     * @return {@link MapIterator}&lt;K, V&gt;
    044     */
    045    public static <K, V> MapIterator<K, V> emptyMapIterator() {
    046        return INSTANCE;
    047    }
    048
    049    /**
    050     * Constructs a new instance.
    051     */
    052    protected EmptyMapIterator() {
    053    }
    054
    055}