/*
 * 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.tinkerpop.gremlin.util.iterator;

import org.apache.tinkerpop.gremlin.process.traversal.util.FastNoSuchElementException;

import java.io.Serializable;
import java.util.Iterator;

/**
 * @author Marko A. Rodriguez (http://markorodriguez.com)
 */
public final class EmptyIterator<S> implements Iterator<S>, Serializable {

    private static final EmptyIterator INSTANCE = new EmptyIterator<>();

    private EmptyIterator() {
    }

    @Override
    public boolean hasNext() {
        return false;
    }

    @Override
    public S next() {
        throw FastNoSuchElementException.instance();
    }

    public static <S> Iterator<S> instance() {
        return INSTANCE;
    }
}