| /** |
| * 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.hadoop.mapreduce; |
| |
| import java.io.IOException; |
| import java.util.Iterator; |
| |
| /** |
| * <code>MarkableIterator</code> is a wrapper iterator class that |
| * implements the {@link MarkableIteratorInterface}. |
| * |
| */ |
| public class MarkableIterator<VALUE> |
| implements MarkableIteratorInterface<VALUE> { |
| |
| MarkableIteratorInterface<VALUE> baseIterator; |
| |
| /** |
| * Create a new iterator layered on the input iterator |
| * @param itr underlying iterator that implements MarkableIteratorInterface |
| */ |
| public MarkableIterator(Iterator<VALUE> itr) { |
| if (!(itr instanceof MarkableIteratorInterface)) { |
| throw new IllegalArgumentException("Input Iterator not markable"); |
| } |
| baseIterator = (MarkableIteratorInterface<VALUE>) itr; |
| } |
| |
| @Override |
| public void mark() throws IOException { |
| baseIterator.mark(); |
| } |
| |
| @Override |
| public void reset() throws IOException { |
| baseIterator.reset(); |
| } |
| |
| @Override |
| public void clearMark() throws IOException { |
| baseIterator.clearMark(); |
| } |
| |
| @Override |
| public boolean hasNext() { |
| return baseIterator.hasNext(); |
| } |
| |
| @Override |
| public VALUE next() { |
| return baseIterator.next(); |
| } |
| |
| @Override |
| public void remove() { |
| throw new UnsupportedOperationException("Remove Not Implemented"); |
| } |
| } |