001/* 002 * Copyright (c) 2007-2017 Xplenty, Inc. All Rights Reserved. 003 * 004 * Project and contact information: http://www.cascading.org/ 005 * 006 * This file is part of the Cascading project. 007 * 008 * Licensed under the Apache License, Version 2.0 (the "License"); 009 * you may not use this file except in compliance with the License. 010 * You may obtain a copy of the License at 011 * 012 * http://www.apache.org/licenses/LICENSE-2.0 013 * 014 * Unless required by applicable law or agreed to in writing, software 015 * distributed under the License is distributed on an "AS IS" BASIS, 016 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 017 * See the License for the specific language governing permissions and 018 * limitations under the License. 019 */ 020 021package cascading.tuple.hadoop.util; 022 023import java.io.IOException; 024 025import cascading.CascadingException; 026import cascading.tuple.io.TuplePair; 027 028/** Class GroupingComparator is an implementation of {@link org.apache.hadoop.io.RawComparator}. */ 029public class GroupingComparator extends DeserializerComparator<TuplePair> 030 { 031 public int compare( byte[] b1, int s1, int l1, byte[] b2, int s2, int l2 ) 032 { 033 try 034 { 035 lhsBuffer.reset( b1, s1, l1 ); 036 rhsBuffer.reset( b2, s2, l2 ); 037 038 // only compare the first tuple in the pair 039 return compareTuples( keyTypes, groupComparators ); 040 } 041 catch( IOException exception ) 042 { 043 throw new CascadingException( exception ); 044 } 045 finally 046 { 047 lhsBuffer.clear(); 048 rhsBuffer.clear(); 049 } 050 } 051 052 public int compare( TuplePair lhs, TuplePair rhs ) 053 { 054 return compareTuples( groupComparators, lhs.getLhs(), rhs.getLhs() ); 055 } 056 }