com.facebook.presto.common.block

Interface UncheckedBlock

All Known Subinterfaces:

Block, BlockBuilder

All Known Implementing Classes:

AbstractArrayBlock, AbstractMapBlock, AbstractRowBlock, AbstractSingleArrayBlock, AbstractSingleMapBlock, AbstractSingleRowBlock, AbstractVariableWidthBlock, AbstractVariableWidthBlockBuilder, ArrayBlock, ArrayBlockBuilder, ByteArrayBlock, ByteArrayBlockBuilder, DictionaryBlock, Int128ArrayBlock, Int128ArrayBlockBuilder, IntArrayBlock, IntArrayBlockBuilder, LazyBlock, LongArrayBlock, LongArrayBlockBuilder, MapBlock, MapBlockBuilder, RowBlock, RowBlockBuilder, RunLengthEncodedBlock, ShortArrayBlock, ShortArrayBlockBuilder, SingleArrayBlockWriter, SingleMapBlock, SingleMapBlockWriter, SingleRowBlock, SingleRowBlockWriter, VariableWidthBlock, VariableWidthBlockBuilder

public interface UncheckedBlock

Accessors for Block which provide for raw indexing into the underlying data structure of the Block. It is intended for hot path use cases where the speed of the boundary checks on Block is a performance bottleneck. Methods in this case must be used with more care, as they may return invalid data if the indexing is not performed with respect to getOffsetBase() and getPositionCount(). Implementations of UncheckedBlock should perform any boundary checks within assert statements so they can be disabled in performance critical deployments by disabling assertions. Example usage:

 
  UncheckedBlock block = ...
  int sum = 0;
  for (int i = block.getOffsetBase(); i < block.getOffsetBase() + block.getPositionCount(); i++) {
      sum += block.getIntUnchecked(i);
  }
 
 

For nested structures, such as dictionaries and RLEs, the indexing is unchecked with respect to the top level block, but not with respect to the inner blocks. If, for performance reasons, it is desired to use unchecked indexing also for the inner blocks, you may unpeel the blocks using existing utilities such as ColumnarArray, ColumnarMap, ColumnarRow and BlockFlattener.

Method Summary

Modifier and Type	Method and Description
default Block	getBlockUnchecked(int internalPosition) Gets a Block value at internalPosition - getOffsetBase().
default byte	getByteUnchecked(int internalPosition) Gets a byte value at internalPosition - getOffsetBase().
default int	getIntUnchecked(int internalPosition) Gets a little endian int value at internalPosition - getOffsetBase().
default long	getLongUnchecked(int internalPosition) Gets a little endian long value at internalPosition - getOffsetBase().
default long	getLongUnchecked(int internalPosition, int offset) Gets a little endian long at offset in the value at internalPosition - getOffsetBase().
int	getOffsetBase()
default short	getShortUnchecked(int internalPosition) Gets a little endian short at value at internalPosition - getOffsetBase().
default int	getSliceLengthUnchecked(int internalPosition) Gets the length of the slice value at internalPosition - getOffsetBase().
default io.airlift.slice.Slice	getSliceUnchecked(int internalPosition, int offset, int length) Gets a slice with offset offset at internalPosition - getOffsetBase().
boolean	isNullUnchecked(int internalPosition)

Method Detail

getByteUnchecked

default byte getByteUnchecked(int internalPosition)

Gets a byte value at internalPosition - getOffsetBase().

getShortUnchecked

default short getShortUnchecked(int internalPosition)

Gets a little endian short at value at internalPosition - getOffsetBase().

getIntUnchecked

default int getIntUnchecked(int internalPosition)

Gets a little endian int value at internalPosition - getOffsetBase().

getLongUnchecked

default long getLongUnchecked(int internalPosition)

Gets a little endian long value at internalPosition - getOffsetBase().

getLongUnchecked

default long getLongUnchecked(int internalPosition,
                              int offset)

Gets a little endian long at offset in the value at internalPosition - getOffsetBase().

getSliceLengthUnchecked

default int getSliceLengthUnchecked(int internalPosition)

Gets the length of the slice value at internalPosition - getOffsetBase(). This method must be implemented if getSliceUnchecked is implemented.

getSliceUnchecked

default io.airlift.slice.Slice getSliceUnchecked(int internalPosition,
                                                 int offset,
                                                 int length)

Gets a slice with offset offset at internalPosition - getOffsetBase().

getBlockUnchecked

default Block getBlockUnchecked(int internalPosition)

Gets a Block value at internalPosition - getOffsetBase().

isNullUnchecked

boolean isNullUnchecked(int internalPosition)

Returns:

true if value at internalPosition - getOffsetBase() is null

getOffsetBase

int getOffsetBase()

Returns:

the internal offset of the underlying data structure of this block