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
019 package org.apache.hadoop.mapred.lib.aggregate;
020
021 import org.apache.hadoop.classification.InterfaceAudience;
022 import org.apache.hadoop.classification.InterfaceStability;
023
024 /**
025 * This class implements a value aggregator that dedupes a sequence of objects.
026 */
027 @InterfaceAudience.Public
028 @InterfaceStability.Stable
029 public class UniqValueCount
030 extends org.apache.hadoop.mapreduce.lib.aggregate.UniqValueCount
031 implements ValueAggregator<Object> {
032 /**
033 * the default constructor
034 *
035 */
036 public UniqValueCount() {
037 super();
038 }
039
040 /**
041 * constructor
042 * @param maxNum the limit in the number of unique values to keep.
043 *
044 */
045 public UniqValueCount(long maxNum) {
046 super(maxNum);
047 }
048 }