/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.facebook.presto.spiller;
import com.facebook.presto.memory.AggregatedMemoryContext;
import com.facebook.presto.operator.SpillContext;
import com.facebook.presto.spi.Page;
import com.facebook.presto.spi.type.Type;
import com.google.common.io.Closer;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import javax.annotation.concurrent.NotThreadSafe;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import static com.google.common.base.Preconditions.checkState;
import static java.util.Objects.requireNonNull;
import static java.util.stream.Collectors.toList;
@NotThreadSafe
public class GenericSpiller
implements Spiller
{
private final List<Type> types;
private final SpillContext spillContext;
private final AggregatedMemoryContext memoryContext;
private final SingleStreamSpillerFactory singleStreamSpillerFactory;
private final Closer closer = Closer.create();
private ListenableFuture<?> previousSpill = Futures.immediateFuture(null);
private final List<SingleStreamSpiller> singleStreamSpillers = new ArrayList<>();
public GenericSpiller(
List<Type> types,
SpillContext spillContext,
AggregatedMemoryContext memoryContext,
SingleStreamSpillerFactory singleStreamSpillerFactory)
{
this.types = requireNonNull(types, "types can not be null");
this.spillContext = requireNonNull(spillContext, "spillContext can not be null");
this.memoryContext = requireNonNull(memoryContext, "memoryContext can not be null");
this.singleStreamSpillerFactory = requireNonNull(singleStreamSpillerFactory, "singleStreamSpillerFactory can not be null");
}
@Override
public ListenableFuture<?> spill(Iterator<Page> pageIterator)
{
checkNoSpillInProgress();
SingleStreamSpiller singleStreamSpiller = singleStreamSpillerFactory.create(types, spillContext, memoryContext.newLocalMemoryContext());
closer.register(singleStreamSpiller);
singleStreamSpillers.add(singleStreamSpiller);
previousSpill = singleStreamSpiller.spill(pageIterator);
return previousSpill;
}
@Override
public List<Iterator<Page>> getSpills()
{
checkNoSpillInProgress();
return singleStreamSpillers.stream()
.map(SingleStreamSpiller::getSpilledPages)
.collect(toList());
}
@Override
public void close()
{
try {
closer.close();
}
catch (IOException e) {
throw new RuntimeException("could not close some single stream spillers", e);
}
}
private void checkNoSpillInProgress()
{
checkState(previousSpill.isDone(), "previous spill still in progress");
}
}