    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
    025    import cascading.CascadingException;
    026    import cascading.tuple.io.IndexTuple;
    027
    028    /** Class GroupingComparator is an implementation of {@link org.apache.hadoop.io.RawComparator}. */
    029    public class CoGroupingComparator extends DeserializerComparator<IndexTuple>
    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          // pop off index
    039          lhsStream.readVInt();
    040          rhsStream.readVInt();
    041
    042          return compareTuples( groupComparators );
    043          }
    044        catch( IOException exception )
    045          {
    046          throw new CascadingException( exception );
    047          }
    048        finally
    049          {
    050          lhsBuffer.clear();
    051          rhsBuffer.clear();
    052          }
    053        }
    054
    055      public int compare( IndexTuple lhs, IndexTuple rhs )
    056        {
    057        return compareTuples( groupComparators, lhs.getTuple(), rhs.getTuple() );
    058        }
    059      }