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     */
018    package org.apache.hadoop.fs;
019    
020    import java.io.IOException;
021    import java.util.NoSuchElementException;
022    /**
023     * An iterator over a collection whose elements need to be fetched remotely
024     */
025    public 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    }