/*
 * 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.commons.collections4.iterators;

import java.util.Iterator;

import org.apache.commons.collections4.ResettableIterator;

Provides an implementation of an empty iterator.

This class provides an implementation of an empty iterator.
This class provides for binary compatibility between Commons Collections
2.1.1 and 3.1 due to issues with IteratorUtils.
Since:
2.1.1 and 3.1/**
 * Provides an implementation of an empty iterator.
 * <p>
 * This class provides an implementation of an empty iterator.
 * This class provides for binary compatibility between Commons Collections
 * 2.1.1 and 3.1 due to issues with <code>IteratorUtils</code>.
 *
 * @since 2.1.1 and 3.1
 */
public class EmptyIterator<E> extends AbstractEmptyIterator<E> implements ResettableIterator<E> {

    
Singleton instance of the iterator.
Since:
3.1/**
     * Singleton instance of the iterator.
     * @since 3.1
     */
    @SuppressWarnings("rawtypes")
    public static final ResettableIterator RESETTABLE_INSTANCE = new EmptyIterator<>();

    
Singleton instance of the iterator.
Since:
2.1.1 and 3.1/**
     * Singleton instance of the iterator.
     * @since 2.1.1 and 3.1
     */
    @SuppressWarnings("rawtypes")
    public static final Iterator INSTANCE = RESETTABLE_INSTANCE;

    
Get a typed resettable empty iterator instance.
Type parameters:
<E> – the element type
Returns:
ResettableIterator<E>/**
     * Get a typed resettable empty iterator instance.
     * @param <E> the element type
     * @return ResettableIterator&lt;E&gt;
     */
    public static <E> ResettableIterator<E> resettableEmptyIterator() {
        return RESETTABLE_INSTANCE;
    }

    
Get a typed empty iterator instance.
Type parameters:
<E> – the element type
Returns:
Iterator<E>/**
     * Get a typed empty iterator instance.
     * @param <E> the element type
     * @return Iterator&lt;E&gt;
     */
    public static <E> Iterator<E> emptyIterator() {
        return INSTANCE;
    }

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

}