    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.collect;
    022
    023    import cascading.tuple.Tuple;
    024    import org.slf4j.Logger;
    025    import org.slf4j.LoggerFactory;
    026
    027    /**
    028     *
    029     */
    030    public interface Spillable
    031      {
    032      interface SpillStrategy
    033        {
    034        boolean doSpill( Spillable spillable, int size );
    035
    036        String getSpillReason( Spillable spillable );
    037        }
    038
    039      interface SpillListener
    040        {
    041        SpillListener NULL = new SpillListener()
    042        {
    043        private final Logger LOG = LoggerFactory.getLogger( SpillListener.class );
    044
    045        @Override
    046        public void notifyWriteSpillBegin( Spillable spillable, int spillSize, String spillReason )
    047          {
    048          LOG.info( "spilling {} tuples in list to spill number {}", spillSize, spillable.spillCount() + 1 );
    049          }
    050
    051        @Override
    052        public void notifyReadSpillBegin( Spillable spillable )
    053          {
    054          }
    055
    056        @Override
    057        public void notifyWriteSpillEnd( SpillableTupleList spillableTupleList, long duration )
    058          {
    059          }
    060        };
    061
    062        void notifyWriteSpillBegin( Spillable spillable, int spillSize, String spillReason );
    063
    064        void notifyWriteSpillEnd( SpillableTupleList spillableTupleList, long duration );
    065
    066        void notifyReadSpillBegin( Spillable spillable );
    067        }
    068
    069      void setGrouping( Tuple group );
    070
    071      Tuple getGrouping();
    072
    073      void setSpillStrategy( SpillStrategy spillStrategy );
    074
    075      void setSpillListener( SpillListener spillListener );
    076
    077      /**
    078       * The number of times this container has spilled data to disk.
    079       *
    080       * @return in int
    081       */
    082      int spillCount();
    083      }