| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.druid.query.aggregation.datasketches.tuple; |
| |
| import org.apache.datasketches.memory.WritableMemory; |
| import org.apache.datasketches.tuple.arrayofdoubles.ArrayOfDoublesSketches; |
| import org.apache.datasketches.tuple.arrayofdoubles.ArrayOfDoublesUpdatableSketch; |
| import org.apache.datasketches.tuple.arrayofdoubles.ArrayOfDoublesUpdatableSketchBuilder; |
| import org.apache.druid.query.aggregation.BufferAggregator; |
| import org.apache.druid.query.monomorphicprocessing.RuntimeShapeInspector; |
| import org.apache.druid.segment.BaseDoubleColumnValueSelector; |
| import org.apache.druid.segment.DimensionSelector; |
| import org.apache.druid.segment.data.IndexedInts; |
| |
| import javax.annotation.Nullable; |
| import java.nio.ByteBuffer; |
| import java.nio.ByteOrder; |
| import java.util.LinkedHashMap; |
| import java.util.List; |
| import java.util.Map; |
| |
| /** |
| * This aggregator builds sketches from raw data. |
| * The input is in the form of a key and array of double values. |
| * The output is {@link org.apache.datasketches.tuple.arrayofdoubles.ArrayOfDoublesSketch}. |
| */ |
| public class ArrayOfDoublesSketchBuildBufferAggregator implements BufferAggregator |
| { |
| private final DimensionSelector keySelector; |
| private final BaseDoubleColumnValueSelector[] valueSelectors; |
| private final int nominalEntries; |
| private final int maxIntermediateSize; |
| @Nullable |
| private double[] values; // not part of the state, but to reuse in aggregate() method |
| |
| |
| private final boolean canLookupUtf8; |
| private final boolean canCacheById; |
| private final LinkedHashMap<Integer, Object> stringCache = new LinkedHashMap<Integer, Object>() |
| { |
| @Override |
| protected boolean removeEldestEntry(Map.Entry eldest) |
| { |
| return size() >= 10; |
| } |
| }; |
| |
| public ArrayOfDoublesSketchBuildBufferAggregator( |
| final DimensionSelector keySelector, |
| final List<BaseDoubleColumnValueSelector> valueSelectors, |
| int nominalEntries, |
| int maxIntermediateSize |
| ) |
| { |
| this.keySelector = keySelector; |
| this.valueSelectors = valueSelectors.toArray(new BaseDoubleColumnValueSelector[0]); |
| this.nominalEntries = nominalEntries; |
| this.maxIntermediateSize = maxIntermediateSize; |
| this.canCacheById = this.keySelector.nameLookupPossibleInAdvance(); |
| this.canLookupUtf8 = this.keySelector.supportsLookupNameUtf8(); |
| } |
| |
| @Override |
| public void init(final ByteBuffer buf, final int position) |
| { |
| final WritableMemory mem = WritableMemory.writableWrap(buf, ByteOrder.LITTLE_ENDIAN); |
| final WritableMemory region = mem.writableRegion(position, maxIntermediateSize); |
| new ArrayOfDoublesUpdatableSketchBuilder().setNominalEntries(nominalEntries) |
| .setNumberOfValues(valueSelectors.length) |
| .setNumberOfValues(valueSelectors.length).build(region); |
| } |
| |
| @Override |
| public void aggregate(final ByteBuffer buf, final int position) |
| { |
| if (values == null) { |
| values = new double[valueSelectors.length]; |
| } |
| |
| for (int i = 0; i < valueSelectors.length; i++) { |
| if (valueSelectors[i].isNull()) { |
| return; |
| } else { |
| values[i] = valueSelectors[i].getDouble(); |
| } |
| } |
| // Wrapping memory and ArrayOfDoublesSketch is inexpensive compared to sketch operations. |
| // Maintaining a cache of wrapped objects per buffer position like in Theta sketch aggregator |
| // might might be considered, but it would increase complexity including relocate() support. |
| final WritableMemory mem = WritableMemory.writableWrap(buf, ByteOrder.LITTLE_ENDIAN); |
| final WritableMemory region = mem.writableRegion(position, maxIntermediateSize); |
| final ArrayOfDoublesUpdatableSketch sketch = ArrayOfDoublesSketches.wrapUpdatableSketch(region); |
| final IndexedInts keys = keySelector.getRow(); |
| if (canLookupUtf8) { |
| for (int i = 0, keysSize = keys.size(); i < keysSize; i++) { |
| final ByteBuffer key; |
| if (canCacheById) { |
| key = (ByteBuffer) stringCache.computeIfAbsent(keys.get(i), keySelector::lookupNameUtf8); |
| } else { |
| key = keySelector.lookupNameUtf8(keys.get(i)); |
| } |
| |
| if (key != null) { |
| byte[] bytes = new byte[key.remaining()]; |
| key.mark(); |
| key.get(bytes); |
| key.reset(); |
| |
| sketch.update(bytes, values); |
| } |
| } |
| } else { |
| for (int i = 0, keysSize = keys.size(); i < keysSize; i++) { |
| final String key; |
| if (canCacheById) { |
| key = (String) stringCache.computeIfAbsent(keys.get(i), keySelector::lookupName); |
| } else { |
| key = keySelector.lookupName(keys.get(i)); |
| } |
| |
| sketch.update(key, values); |
| } |
| } |
| } |
| |
| /** |
| * The returned sketch is a separate instance of ArrayOfDoublesCompactSketch |
| * representing the current state of the aggregation, and is not affected by consequent |
| * aggregate() calls |
| */ |
| @Override |
| public Object get(final ByteBuffer buf, final int position) |
| { |
| final WritableMemory mem = WritableMemory.writableWrap(buf, ByteOrder.LITTLE_ENDIAN); |
| final WritableMemory region = mem.writableRegion(position, maxIntermediateSize); |
| final ArrayOfDoublesUpdatableSketch sketch = (ArrayOfDoublesUpdatableSketch) ArrayOfDoublesSketches |
| .wrapSketch(region); |
| return sketch.compact(); |
| } |
| |
| @Override |
| public float getFloat(final ByteBuffer buf, final int position) |
| { |
| throw new UnsupportedOperationException("Not implemented"); |
| } |
| |
| @Override |
| public long getLong(final ByteBuffer buf, final int position) |
| { |
| throw new UnsupportedOperationException("Not implemented"); |
| } |
| |
| @Override |
| public void close() |
| { |
| values = null; |
| } |
| |
| @Override |
| public void inspectRuntimeShape(final RuntimeShapeInspector inspector) |
| { |
| inspector.visit("keySelector", keySelector); |
| inspector.visit("valueSelectors", valueSelectors); |
| } |
| } |