001/*
002 * Copyright (c) 2007-2015 Concurrent, 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;
024import java.util.Comparator;
025
026import cascading.CascadingException;
027import cascading.tuple.io.TuplePair;
028import org.apache.hadoop.conf.Configuration;
029
030/** Class TuplePairComparator is an implementation of {@link org.apache.hadoop.io.RawComparator}. */
031public class GroupingSortingComparator extends DeserializerComparator<TuplePair>
032  {
033  Comparator[] sortComparators;
034
035  @Override
036  public void setConf( Configuration conf )
037    {
038    super.setConf( conf );
039
040    if( conf == null )
041      return;
042
043    sortComparators = deserializeComparatorsFor( "cascading.sort.comparator" );
044    sortComparators = delegatingComparatorsFor( sortComparators );
045    }
046
047  public int compare( byte[] b1, int s1, int l1, byte[] b2, int s2, int l2 )
048    {
049    try
050      {
051      lhsBuffer.reset( b1, s1, l1 );
052      rhsBuffer.reset( b2, s2, l2 );
053
054      int c = compareTuples( groupComparators );
055
056      if( c != 0 )
057        return c;
058
059      return compareTuples( sortComparators );
060      }
061    catch( IOException exception )
062      {
063      throw new CascadingException( exception );
064      }
065    finally
066      {
067      lhsBuffer.clear();
068      rhsBuffer.clear();
069      }
070    }
071
072  public int compare( TuplePair lhs, TuplePair rhs )
073    {
074    int c = compareTuples( groupComparators, lhs.getLhs(), rhs.getLhs() );
075
076    if( c != 0 )
077      return c;
078
079    return compareTuples( sortComparators, lhs.getRhs(), rhs.getRhs() );
080    }
081  }