| /* |
| * 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.groupby.epinephelinae.column; |
| |
| import com.google.common.base.Preconditions; |
| import org.apache.druid.common.config.NullHandling; |
| import org.apache.druid.query.groupby.ResultRow; |
| import org.apache.druid.query.groupby.epinephelinae.Grouper; |
| import org.apache.druid.query.ordering.StringComparator; |
| import org.apache.druid.query.ordering.StringComparators; |
| import org.apache.druid.segment.ColumnValueSelector; |
| import org.apache.druid.segment.DimensionSelector; |
| import org.apache.druid.segment.column.ColumnCapabilities; |
| import org.apache.druid.segment.data.IndexedInts; |
| |
| import javax.annotation.Nullable; |
| import java.nio.ByteBuffer; |
| import java.util.function.IntFunction; |
| |
| public class StringGroupByColumnSelectorStrategy implements GroupByColumnSelectorStrategy |
| { |
| @Nullable |
| private final ColumnCapabilities capabilities; |
| |
| @Nullable |
| private final IntFunction<String> dictionaryLookup; |
| |
| public StringGroupByColumnSelectorStrategy(IntFunction<String> dictionaryLookup, ColumnCapabilities capabilities) |
| { |
| this.dictionaryLookup = dictionaryLookup; |
| this.capabilities = capabilities; |
| } |
| |
| @Override |
| public int getGroupingKeySize() |
| { |
| return Integer.BYTES; |
| } |
| |
| @Override |
| public void processValueFromGroupingKey( |
| GroupByColumnSelectorPlus selectorPlus, |
| ByteBuffer key, |
| ResultRow resultRow, |
| int keyBufferPosition |
| ) |
| { |
| final int id = key.getInt(keyBufferPosition); |
| |
| // GROUP_BY_MISSING_VALUE is used to indicate empty rows, which are omitted from the result map. |
| if (id != GROUP_BY_MISSING_VALUE) { |
| resultRow.set( |
| selectorPlus.getResultRowPosition(), |
| ((DimensionSelector) selectorPlus.getSelector()).lookupName(id) |
| ); |
| } else { |
| resultRow.set(selectorPlus.getResultRowPosition(), NullHandling.defaultStringValue()); |
| } |
| } |
| |
| @Override |
| public int initColumnValues(ColumnValueSelector selector, int columnIndex, Object[] valuess) |
| { |
| DimensionSelector dimSelector = (DimensionSelector) selector; |
| IndexedInts row = dimSelector.getRow(); |
| valuess[columnIndex] = row; |
| return 0; |
| } |
| |
| /** |
| * Writes a dictionary ID to the grouping key. |
| * |
| * Protected so subclasses can access it, like {@link DictionaryBuildingStringGroupByColumnSelectorStrategy}. |
| */ |
| protected void writeToKeyBuffer(int keyBufferPosition, int dictId, ByteBuffer keyBuffer) |
| { |
| keyBuffer.putInt(keyBufferPosition, dictId); |
| } |
| |
| @Override |
| public int writeToKeyBuffer(int keyBufferPosition, ColumnValueSelector selector, ByteBuffer keyBuffer) |
| { |
| final DimensionSelector dimSelector = (DimensionSelector) selector; |
| final IndexedInts row = dimSelector.getRow(); |
| Preconditions.checkState(row.size() < 2, "Not supported for multi-value dimensions"); |
| final int dictId = row.size() == 1 ? row.get(0) : GROUP_BY_MISSING_VALUE; |
| keyBuffer.putInt(keyBufferPosition, dictId); |
| return 0; |
| } |
| |
| @Override |
| public void initGroupingKeyColumnValue( |
| int keyBufferPosition, |
| int dimensionIndex, |
| Object rowObj, |
| ByteBuffer keyBuffer, |
| int[] stack |
| ) |
| { |
| IndexedInts row = (IndexedInts) rowObj; |
| int rowSize = row.size(); |
| |
| initializeGroupingKeyV2Dimension(row, rowSize, keyBuffer, keyBufferPosition); |
| stack[dimensionIndex] = rowSize == 0 ? 0 : 1; |
| } |
| |
| @Override |
| public boolean checkRowIndexAndAddValueToGroupingKey( |
| int keyBufferPosition, |
| Object rowObj, |
| int rowValIdx, |
| ByteBuffer keyBuffer |
| ) |
| { |
| IndexedInts row = (IndexedInts) rowObj; |
| int rowSize = row.size(); |
| |
| if (rowValIdx < rowSize) { |
| keyBuffer.putInt( |
| keyBufferPosition, |
| row.get(rowValIdx) |
| ); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| private void initializeGroupingKeyV2Dimension( |
| final IndexedInts values, |
| final int rowSize, |
| final ByteBuffer keyBuffer, |
| final int keyBufferPosition |
| ) |
| { |
| if (rowSize == 0) { |
| keyBuffer.putInt(keyBufferPosition, GROUP_BY_MISSING_VALUE); |
| } else { |
| keyBuffer.putInt(keyBufferPosition, values.get(0)); |
| } |
| } |
| |
| @Override |
| public Grouper.BufferComparator bufferComparator(int keyBufferPosition, @Nullable StringComparator stringComparator) |
| { |
| final boolean canCompareInts = |
| capabilities != null && |
| capabilities.hasBitmapIndexes() && |
| capabilities.areDictionaryValuesSorted().and(capabilities.areDictionaryValuesUnique()).isTrue(); |
| final StringComparator comparator = stringComparator == null ? StringComparators.LEXICOGRAPHIC : stringComparator; |
| if (canCompareInts && StringComparators.LEXICOGRAPHIC.equals(comparator)) { |
| return (lhsBuffer, rhsBuffer, lhsPosition, rhsPosition) -> Integer.compare( |
| lhsBuffer.getInt(lhsPosition + keyBufferPosition), |
| rhsBuffer.getInt(rhsPosition + keyBufferPosition) |
| ); |
| } else { |
| Preconditions.checkState(dictionaryLookup != null, "null dictionary lookup"); |
| return (lhsBuffer, rhsBuffer, lhsPosition, rhsPosition) -> { |
| String lhsStr = dictionaryLookup.apply(lhsBuffer.getInt(lhsPosition + keyBufferPosition)); |
| String rhsStr = dictionaryLookup.apply(rhsBuffer.getInt(rhsPosition + keyBufferPosition)); |
| return comparator.compare(lhsStr, rhsStr); |
| }; |
| } |
| } |
| |
| @Override |
| public void reset() |
| { |
| // Nothing to do. |
| } |
| } |