    001    /*
    002     * Copyright (c) 2007-2014 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
    021    package cascading.tuple.hadoop.util;
    022
    023    import java.io.IOException;
    024    import java.util.Comparator;
    025
    026    import cascading.CascadingException;
    027    import cascading.tuple.io.TuplePair;
    028    import org.apache.hadoop.conf.Configuration;
    029
    030    /** Class TuplePairComparator is an implementation of {@link org.apache.hadoop.io.RawComparator}. */
    031    public 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      }