001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.fs;
019
020import java.io.IOException;
021import java.util.NoSuchElementException;
022/**
023 * An iterator over a collection whose elements need to be fetched remotely
024 */
025public interface RemoteIterator<E> {
026  /**
027   * Returns <tt>true</tt> if the iteration has more elements.
028   *
029   * @return <tt>true</tt> if the iterator has more elements.
030   * @throws IOException if any IO error occurs
031   */
032  boolean hasNext() throws IOException;
033
034  /**
035   * Returns the next element in the iteration.
036   *
037   * @return the next element in the iteration.
038   * @throws NoSuchElementException iteration has no more elements.
039   * @throws IOException if any IO error occurs
040   */
041  E next() throws IOException;
042}