/*
* 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.operator;
import com.facebook.presto.block.Block;
import com.facebook.presto.block.BlockBuilder;
import com.facebook.presto.block.BlockCursor;
import com.facebook.presto.block.uncompressed.UncompressedBlock;
import com.facebook.presto.operator.SetBuilderOperator.SetSupplier;
import com.facebook.presto.tuple.TupleInfo;
import com.google.common.collect.ImmutableList;
import com.google.common.util.concurrent.ListenableFuture;
import io.airlift.slice.Slices;
import java.util.List;
import static com.facebook.presto.util.MoreFutures.tryGetUnchecked;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
public class HashSemiJoinOperator
implements Operator
{
private final OperatorContext operatorContext;
public static class HashSemiJoinOperatorFactory
implements OperatorFactory
{
private final int operatorId;
private final SetSupplier setSupplier;
private final List<TupleInfo> probeTupleInfos;
private final int probeJoinChannel;
private final List<TupleInfo> tupleInfos;
private boolean closed;
public HashSemiJoinOperatorFactory(int operatorId, SetSupplier setSupplier, List<TupleInfo> probeTupleInfos, int probeJoinChannel)
{
this.operatorId = operatorId;
this.setSupplier = setSupplier;
this.probeTupleInfos = probeTupleInfos;
checkArgument(probeJoinChannel >= 0, "probeJoinChannel is negative");
this.probeJoinChannel = probeJoinChannel;
this.tupleInfos = ImmutableList.<TupleInfo>builder()
.addAll(probeTupleInfos)
.add(TupleInfo.SINGLE_BOOLEAN)
.build();
}
@Override
public List<TupleInfo> getTupleInfos()
{
return tupleInfos;
}
@Override
public Operator createOperator(DriverContext driverContext)
{
checkState(!closed, "Factory is already closed");
OperatorContext operatorContext = driverContext.addOperatorContext(operatorId, HashBuilderOperator.class.getSimpleName());
return new HashSemiJoinOperator(operatorContext, setSupplier, probeTupleInfos, probeJoinChannel);
}
@Override
public void close()
{
closed = true;
}
}
private final int probeJoinChannel;
private final List<TupleInfo> tupleInfos;
private final ListenableFuture<ChannelSet> channelSetFuture;
private ChannelSet channelSet;
private Page outputPage;
private boolean finishing;
public HashSemiJoinOperator(OperatorContext operatorContext, SetSupplier channelSetFuture, List<TupleInfo> probeTupleInfos, int probeJoinChannel)
{
this.operatorContext = checkNotNull(operatorContext, "operatorContext is null");
// todo pass in desired projection
checkNotNull(channelSetFuture, "hashProvider is null");
checkNotNull(probeTupleInfos, "probeTupleInfos is null");
checkArgument(probeJoinChannel >= 0, "probeJoinChannel is negative");
checkArgument(probeTupleInfos.get(probeJoinChannel).getFieldCount() == 1, "Semi join currently only support simple types");
this.channelSetFuture = channelSetFuture.getChannelSet();
this.probeJoinChannel = probeJoinChannel;
this.tupleInfos = ImmutableList.<TupleInfo>builder()
.addAll(probeTupleInfos)
.add(TupleInfo.SINGLE_BOOLEAN)
.build();
}
@Override
public OperatorContext getOperatorContext()
{
return operatorContext;
}
@Override
public List<TupleInfo> getTupleInfos()
{
return tupleInfos;
}
@Override
public void finish()
{
finishing = true;
}
@Override
public boolean isFinished()
{
return finishing && outputPage == null;
}
@Override
public ListenableFuture<?> isBlocked()
{
return channelSetFuture;
}
@Override
public boolean needsInput()
{
if (finishing || outputPage != null) {
return false;
}
if (channelSet == null) {
channelSet = tryGetUnchecked(channelSetFuture);
}
return channelSet != null;
}
@Override
public void addInput(Page page)
{
checkNotNull(page, "page is null");
checkState(!finishing, "Operator is finishing");
checkState(channelSet != null, "Set has not been built yet");
checkState(outputPage == null, "Operator still has pending output");
// update hashing strategy to use probe block
UncompressedBlock probeJoinBlock = (UncompressedBlock) page.getBlock(probeJoinChannel);
channelSet.setLookupSlice(probeJoinBlock.getSlice());
// create the block builder for the new boolean column
// we know the exact size required for the block
int blockSize = page.getPositionCount() * TupleInfo.SINGLE_BOOLEAN.getFixedSize();
BlockBuilder blockBuilder = new BlockBuilder(TupleInfo.SINGLE_BOOLEAN, blockSize, Slices.allocate(blockSize).getOutput());
BlockCursor probeJoinCursor = probeJoinBlock.cursor();
for (int position = 0; position < page.getPositionCount(); position++) {
checkState(probeJoinCursor.advanceNextPosition());
if (probeJoinCursor.isNull(0)) {
blockBuilder.appendNull();
}
else {
boolean contains = channelSet.contains(probeJoinCursor);
if (!contains && channelSet.containsNull()) {
blockBuilder.appendNull();
}
else {
blockBuilder.append(contains);
}
}
}
// add the new boolean column to the page
Block[] sourceBlocks = page.getBlocks();
Block[] outputBlocks = new Block[sourceBlocks.length + 1]; // +1 for the single boolean output channel
System.arraycopy(sourceBlocks, 0, outputBlocks, 0, sourceBlocks.length);
outputBlocks[sourceBlocks.length] = blockBuilder.build();
outputPage = new Page(outputBlocks);
}
@Override
public Page getOutput()
{
Page result = outputPage;
outputPage = null;
return result;
}
}