Package org.apache.druid.query.groupby.epinephelinae.column

Class KeyMappingMultiValueGroupByColumnSelectorStrategy

java.lang.Object

org.apache.druid.query.groupby.epinephelinae.column.KeyMappingMultiValueGroupByColumnSelectorStrategy

All Implemented Interfaces:

ColumnSelectorStrategy, GroupByColumnSelectorStrategy

Direct Known Subclasses:

KeyMappingMultiValueGroupByColumnSelectorStrategy.DictionaryBuilding, KeyMappingMultiValueGroupByColumnSelectorStrategy.PrebuiltDictionary

public abstract class KeyMappingMultiValueGroupByColumnSelectorStrategy
extends Object
implements GroupByColumnSelectorStrategy

Like KeyMappingGroupByColumnSelectorStrategy, but for multi-value dimensions, i.e. strings. It can only handle DimensionSelector

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	KeyMappingMultiValueGroupByColumnSelectorStrategy.DictionaryBuilding
static class	KeyMappingMultiValueGroupByColumnSelectorStrategy.PrebuiltDictionary

Field Summary

Fields inherited from interface org.apache.druid.query.groupby.epinephelinae.column.GroupByColumnSelectorStrategy

GROUP_BY_MISSING_VALUE

Constructor Summary

Constructors

Constructor	Description
KeyMappingMultiValueGroupByColumnSelectorStrategy()

Method Summary

Modifier and Type	Method	Description
boolean	checkRowIndexAndAddValueToGroupingKey(int keyBufferPosition, Object rowObj, int rowValIdx, ByteBuffer keyBuffer)	If rowValIdx is less than the size of rowObj (haven't handled all of the row values): First, read the value at rowValIdx from a rowObj and write that value to the keyBuffer at keyBufferPosition.
static GroupByColumnSelectorStrategy	create(ColumnCapabilities capabilities, DimensionSelector dimensionSelector)
int	getGroupingKeySizeBytes()	Return the size, in bytes, of this dimension's values in the grouping key.
void	initGroupingKeyColumnValue(int keyBufferPosition, int dimensionIndex, Object rowObj, ByteBuffer keyBuffer, int[] stack)	Read the first value within a row values object (e.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.druid.query.groupby.epinephelinae.column.GroupByColumnSelectorStrategy

bufferComparator, initColumnValues, processValueFromGroupingKey, reset, writeToKeyBuffer

Constructor Details

KeyMappingMultiValueGroupByColumnSelectorStrategy

public KeyMappingMultiValueGroupByColumnSelectorStrategy()

Method Details

create

public static GroupByColumnSelectorStrategy create(ColumnCapabilities capabilities,
 DimensionSelector dimensionSelector)

getGroupingKeySizeBytes

public int getGroupingKeySizeBytes()

Description copied from interface: GroupByColumnSelectorStrategy

Return the size, in bytes, of this dimension's values in the grouping key. For example, a String implementation would return 4, the size of an int.

Specified by:

getGroupingKeySizeBytes in interface GroupByColumnSelectorStrategy

Returns:

size, in bytes, of this dimension's values in the grouping key.

initGroupingKeyColumnValue

public void initGroupingKeyColumnValue(int keyBufferPosition,
 int dimensionIndex,
 Object rowObj,
 ByteBuffer keyBuffer,
 int[] stack)

Description copied from interface: GroupByColumnSelectorStrategy

Read the first value within a row values object (e. g. IndexedInts, as the value in a dictionary-encoded string column) and write that value to the keyBuffer at keyBufferPosition. If the row size is 0 (e. g. IndexedInts.size()), write GroupByColumnSelectorStrategy.GROUP_BY_MISSING_VALUE instead. If the size of the row is > 0, write 1 to stack[] at columnIndex, otherwise write 0.

Specified by:

initGroupingKeyColumnValue in interface GroupByColumnSelectorStrategy

Parameters:

keyBufferPosition - Starting offset for this column's value within the grouping key.

dimensionIndex - Index of this dimension within the stack array

rowObj - Row value object for this column

keyBuffer - grouping key

stack - array containing the current within-row value index for each column

checkRowIndexAndAddValueToGroupingKey

public boolean checkRowIndexAndAddValueToGroupingKey(int keyBufferPosition,
 Object rowObj,
 int rowValIdx,
 ByteBuffer keyBuffer)

Description copied from interface: GroupByColumnSelectorStrategy

If rowValIdx is less than the size of rowObj (haven't handled all of the row values): First, read the value at rowValIdx from a rowObj and write that value to the keyBuffer at keyBufferPosition. Then return true. This method assumes that the size increase associated with the dictionary building has occurred already when calling GroupByColumnSelectorStrategy.initColumnValues(org.apache.druid.segment.ColumnValueSelector, int, java.lang.Object[]) Otherwise, return false.

Specified by:

checkRowIndexAndAddValueToGroupingKey in interface GroupByColumnSelectorStrategy

Parameters:

keyBufferPosition - Starting offset for this column's value within the grouping key.

rowObj - Row value object for this column (e.g., IndexedInts)

rowValIdx - Index of the current value being grouped on within the row

keyBuffer - grouping key

Returns:

true if rowValIdx < size of rowObj, false otherwise