io.trino.operator.NoChannelGroupByHash Maven / Gradle / Ivy
/*
* 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 io.trino.operator;
import io.trino.spi.Page;
import io.trino.spi.PageBuilder;
import static io.airlift.slice.SizeOf.instanceSize;
public class NoChannelGroupByHash
implements GroupByHash
{
private static final int INSTANCE_SIZE = instanceSize(NoChannelGroupByHash.class);
private int groupCount;
@Override
public long getEstimatedSize()
{
return INSTANCE_SIZE;
}
@Override
public int getGroupCount()
{
return groupCount;
}
@Override
public void appendValuesTo(int groupId, PageBuilder pageBuilder)
{
throw new UnsupportedOperationException("NoChannelGroupByHash does not support appendValuesTo");
}
@Override
public Work> addPage(Page page)
{
updateGroupCount(page);
// create a dump work whose result is never used.
return new CompletedWork<>(0);
}
@Override
public Work getGroupIds(Page page)
{
updateGroupCount(page);
return new CompletedWork<>(new int[page.getPositionCount()]);
}
@Override
public long getRawHash(int groupId)
{
throw new UnsupportedOperationException("NoChannelGroupByHash does not support getHashCollisions");
}
@Override
public int getCapacity()
{
return 2;
}
private void updateGroupCount(Page page)
{
if (page.getPositionCount() > 0 && groupCount == 0) {
groupCount = 1;
}
}
}