Class ArrayNumericGroupByColumnSelectorStrategy<T extends Comparable>
- java.lang.Object
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- org.apache.druid.query.groupby.epinephelinae.column.ArrayNumericGroupByColumnSelectorStrategy<T>
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- All Implemented Interfaces:
ColumnSelectorStrategy
,GroupByColumnSelectorStrategy
- Direct Known Subclasses:
ArrayDoubleGroupByColumnSelectorStrategy
,ArrayLongGroupByColumnSelectorStrategy
public abstract class ArrayNumericGroupByColumnSelectorStrategy<T extends Comparable> extends Object implements GroupByColumnSelectorStrategy
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Field Summary
Fields Modifier and Type Field Description protected List<List<T>>
dictionary
protected long
estimatedFootprint
protected static int
GROUP_BY_MISSING_VALUE
protected it.unimi.dsi.fastutil.objects.Object2IntMap<List<T>>
reverseDictionary
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Constructor Summary
Constructors Constructor Description ArrayNumericGroupByColumnSelectorStrategy(int valueFootprint)
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Method Summary
All Methods Instance Methods Abstract Methods Concrete Methods Modifier and Type Method Description protected int
addToIndexedDictionary(List<T> t)
Grouper.BufferComparator
bufferComparator(int keyBufferPosition, StringComparator stringComparator)
Return BufferComparator for values written using this strategy when limit is pushed down to segment scan.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.protected abstract int
computeDictionaryId(ColumnValueSelector selector)
int
getGroupingKeySize()
Return the size, in bytes, of this dimension's values in the grouping key.int
initColumnValues(ColumnValueSelector selector, int columnIndex, Object[] valuess)
Retrieve a row object from theColumnValueSelector
and put it in valuess at columnIndex.void
initGroupingKeyColumnValue(int keyBufferPosition, int dimensionIndex, Object rowObj, ByteBuffer keyBuffer, int[] stack)
Read the first value within a row values object (e.void
processValueFromGroupingKey(GroupByColumnSelectorPlus selectorPlus, ByteBuffer key, ResultRow resultRow, int keyBufferPosition)
Read a value from a grouping key and add it to the group by query result row, using the output name specified in a DimensionSpec.void
reset()
Reset any internal state held by this selector.int
writeToKeyBuffer(int keyBufferPosition, ColumnValueSelector selector, ByteBuffer keyBuffer)
Write a single object from the given selector to the keyBuffer at keyBufferPosition.
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Field Detail
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GROUP_BY_MISSING_VALUE
protected static final int GROUP_BY_MISSING_VALUE
- See Also:
- Constant Field Values
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dictionary
protected final List<List<T extends Comparable>> dictionary
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reverseDictionary
protected final it.unimi.dsi.fastutil.objects.Object2IntMap<List<T extends Comparable>> reverseDictionary
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estimatedFootprint
protected long estimatedFootprint
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Method Detail
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getGroupingKeySize
public int getGroupingKeySize()
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:
getGroupingKeySize
in interfaceGroupByColumnSelectorStrategy
- Returns:
- size, in bytes, of this dimension's values in the grouping key.
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processValueFromGroupingKey
public void processValueFromGroupingKey(GroupByColumnSelectorPlus selectorPlus, ByteBuffer key, ResultRow resultRow, int keyBufferPosition)
Description copied from interface:GroupByColumnSelectorStrategy
Read a value from a grouping key and add it to the group by query result row, using the output name specified in a DimensionSpec. An implementation may choose to not add anything to the result row (e.g., as the String implementation does for empty rows) selectorPlus provides access to: - the keyBufferPosition offset from which to read the value - the dimension value selector - the DimensionSpec for this dimension from the query- Specified by:
processValueFromGroupingKey
in interfaceGroupByColumnSelectorStrategy
- Parameters:
selectorPlus
- dimension info containing the key offset, value selector, and dimension speckey
- grouping keyresultRow
- result row for the group by query being servedkeyBufferPosition
- buffer position for the grouping key, added to support chaining multipleColumnSelectorStrategy
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initColumnValues
public int initColumnValues(ColumnValueSelector selector, int columnIndex, Object[] valuess)
Description copied from interface:GroupByColumnSelectorStrategy
Retrieve a row object from theColumnValueSelector
and put it in valuess at columnIndex.- Specified by:
initColumnValues
in interfaceGroupByColumnSelectorStrategy
- Parameters:
selector
- Value selector for a column.columnIndex
- Index of the column within the row values arrayvaluess
- Row values array, one index per column- Returns:
- estimated increase in internal state footprint, in bytes, as a result of this operation. May be zero if memory did not increase as a result of this operation. Will not be negative.
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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()
), writeGroupByColumnSelectorStrategy.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 interfaceGroupByColumnSelectorStrategy
- Parameters:
keyBufferPosition
- Starting offset for this column's value within the grouping key.dimensionIndex
- Index of this dimension within thestack
arrayrowObj
- Row value object for this columnkeyBuffer
- grouping keystack
- array containing the current within-row value index for each column
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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 Otherwise, return false.- Specified by:
checkRowIndexAndAddValueToGroupingKey
in interfaceGroupByColumnSelectorStrategy
- 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 rowkeyBuffer
- grouping key- Returns:
- true if rowValIdx < size of rowObj, false otherwise
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computeDictionaryId
protected abstract int computeDictionaryId(ColumnValueSelector selector)
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writeToKeyBuffer
public int writeToKeyBuffer(int keyBufferPosition, ColumnValueSelector selector, ByteBuffer keyBuffer)
Description copied from interface:GroupByColumnSelectorStrategy
Write a single object from the given selector to the keyBuffer at keyBufferPosition. The reading column must have a single value. The position of the keyBuffer may be modified.- Specified by:
writeToKeyBuffer
in interfaceGroupByColumnSelectorStrategy
- Parameters:
keyBufferPosition
- starting offset for this column's value within the grouping keyselector
- selector to retrieve row value object fromkeyBuffer
- grouping key- Returns:
- estimated increase in internal state footprint, in bytes, as a result of this operation. May be zero if memory did not increase as a result of this operation. Will not be negative.
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bufferComparator
public Grouper.BufferComparator bufferComparator(int keyBufferPosition, @Nullable StringComparator stringComparator)
Description copied from interface:GroupByColumnSelectorStrategy
Return BufferComparator for values written using this strategy when limit is pushed down to segment scan.- Specified by:
bufferComparator
in interfaceGroupByColumnSelectorStrategy
- Parameters:
keyBufferPosition
- starting offset for this column's value within the grouping keystringComparator
- stringComparator from LimitSpec for this column. If this is null, implementations will use theStringComparators.LEXICOGRAPHIC
comparator.- Returns:
- BufferComparator for comparing values written
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reset
public void reset()
Description copied from interface:GroupByColumnSelectorStrategy
Reset any internal state held by this selector. After this method is called, any row objects or key objects generated by any methods of this class must be considered unreadable. CallingGroupByColumnSelectorStrategy.processValueFromGroupingKey(org.apache.druid.query.groupby.epinephelinae.column.GroupByColumnSelectorPlus, java.nio.ByteBuffer, org.apache.druid.query.groupby.ResultRow, int)
on that memory has undefined behavior.- Specified by:
reset
in interfaceGroupByColumnSelectorStrategy
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