org.apache.drill.exec.vector

Class BitVector

java.lang.Object

org.apache.drill.exec.vector.BaseValueVector

org.apache.drill.exec.vector.BaseDataValueVector

org.apache.drill.exec.vector.BitVector

All Implemented Interfaces:

Closeable, AutoCloseable, Iterable<ValueVector>, FixedWidthVector, ValueVector

public final class BitVector
extends BaseDataValueVector
implements FixedWidthVector

Bit implements a vector of bit-width values. Elements in the vector are accessed by position from the logical start of the vector. The width of each element is 1 bit. The equivalent Java primitive is an int containing the value '0' or '1'.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	BitVector.Accessor
class	BitVector.Mutator MutableBit implements a vector of bit-width values.

Nested classes/interfaces inherited from class org.apache.drill.exec.vector.BaseValueVector

BaseValueVector.BaseAccessor, BaseValueVector.BaseMutator

Field Summary

Fields

Modifier and Type	Field and Description
static int	MAX_CAPACITY Maximum number of values that this fixed-width vector can hold and stay below the maximum vector size limit.
static int	MAX_COUNT Maximum number of values that this fixed-width vector can hold and stay below the maximum vector size limit and/or stay below the maximum item count.
static int	NET_MAX_SIZE Actual maximum vector size, in bytes, given the number of fixed-width values that either fit in the maximum overall vector size, or that is no larger than the maximum vector item count.
static int	VALUE_WIDTH Width of each fixed-width value.

Fields inherited from class org.apache.drill.exec.vector.BaseDataValueVector

data, emptyByteArray

Fields inherited from class org.apache.drill.exec.vector.BaseValueVector

allocator, field, INITIAL_VALUE_ALLOCATION, MAX_ALLOCATION_SIZE

Fields inherited from interface org.apache.drill.exec.vector.ValueVector

BITS_VECTOR_NAME, MAX_BUFFER_SIZE, MAX_ROW_COUNT, MIN_ROW_COUNT, OFFSETS_VECTOR_NAME, VALUES_VECTOR_NAME

Constructor Summary

Constructors

Constructor and Description
BitVector(MaterializedField field, BufferAllocator allocator)

Method Summary

Modifier and Type	Method and Description
void	allocateNew() Allocate new buffers.
void	allocateNew(int valueCount) Allocate a new memory space for this vector.
boolean	allocateNewSafe() Allocates new buffers.
void	clear() Release the underlying DrillBuf and reset the ValueVector to empty.
void	copyEntry(int toIndex, ValueVector from, int fromIndex)
void	copyFrom(int inIndex, int outIndex, BitVector from)
void	copyFromSafe(int inIndex, int outIndex, BitVector from)
void	exchange(ValueVector other) Exchange state with another value vector of the same type.
BitVector.Accessor	getAccessor() Returns an accessor that is used to read from this vector instance.
int	getBufferSize() Returns the number of bytes that is used by this vector instance.
int	getBufferSizeFor(int valueCount) Returns the number of bytes that is used by this vector if it holds the given number of values.
BitVector.Mutator	getMutator() Returns an mutator that is used to write to this vector instance.
int	getPayloadByteCount(int valueCount) Return the number of value bytes consumed by actual data.
FieldReader	getReader() Returns a field reader that supports reading values from this vector.
static int	getSizeFromCount(int valueCount)
TransferPair	getTransferPair(BufferAllocator allocator) Returns a transfer pair, creating a new target vector of the same type.
TransferPair	getTransferPair(String ref, BufferAllocator allocator)
int	getValueCapacity() Returns the maximum number of values that can be stored in this vector instance.
int	getValueWidth() The width of a record in bytes.
void	load(UserBitShared.SerializedField metadata, DrillBuf buffer) Load the data provided in the buffer.
TransferPair	makeTransferPair(ValueVector to) Returns a new transfer pair that is used to transfer underlying buffers into the target vector.
void	reAlloc() Allocate new buffer with double capacity, and copy data into the new buffer.
DrillBuf	reallocRaw(int newAllocationSize) Core of vector allocation.
void	reset() This method has a similar effect of allocateNew() without actually clearing and reallocating the value vector.
void	setInitialCapacity(int valueCount) Set the initial record capacity
void	splitAndTransferTo(int startIndex, int length, BitVector target)
void	toNullable(ValueVector nullableVector) Convert a non-nullable vector to nullable by shuffling the data from one to the other.
void	transferTo(BitVector target)
void	zeroVector() Zero out the underlying buffer backing this vector.

Methods inherited from class org.apache.drill.exec.vector.BaseDataValueVector

close, collectLedgers, getAllocatedSize, getBuffer, getBuffers

Methods inherited from class org.apache.drill.exec.vector.BaseValueVector

checkBufRefs, fillBitsVector, getAllocator, getField, getField, getMetadata, getMetadataBuilder, iterator, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.drill.exec.vector.ValueVector

close, collectLedgers, getAllocatedSize, getAllocator, getBuffers, getField, getMetadata

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Field Detail

VALUE_WIDTH

public static final int VALUE_WIDTH

Width of each fixed-width value.

See Also:

Constant Field Values

MAX_CAPACITY

public static final int MAX_CAPACITY

Maximum number of values that this fixed-width vector can hold and stay below the maximum vector size limit. This is the limit enforced when the vector is used to hold values in a repeated vector.

MAX_COUNT

public static final int MAX_COUNT

Maximum number of values that this fixed-width vector can hold and stay below the maximum vector size limit and/or stay below the maximum item count. This is the limit enforced when the vector is used to hold required or nullable values.

NET_MAX_SIZE

public static final int NET_MAX_SIZE

Actual maximum vector size, in bytes, given the number of fixed-width values that either fit in the maximum overall vector size, or that is no larger than the maximum vector item count.

Constructor Detail

BitVector

public BitVector(MaterializedField field,
                 BufferAllocator allocator)

Method Detail

getReader

public FieldReader getReader()

Description copied from interface: ValueVector

Returns a field reader that supports reading values from this vector.

Specified by:

getReader in interface ValueVector

getBufferSize

public int getBufferSize()

Description copied from interface: ValueVector

Returns the number of bytes that is used by this vector instance. This is a bit of a misnomer. Returns the number of bytes used by data in this instance.

Specified by:

getBufferSize in interface ValueVector

Overrides:

getBufferSize in class BaseDataValueVector

getBufferSizeFor

public int getBufferSizeFor(int valueCount)

Description copied from interface: ValueVector

Returns the number of bytes that is used by this vector if it holds the given number of values. The result will be the same as if Mutator.setValueCount() were called, followed by calling getBufferSize(), but without any of the closing side-effects that setValueCount() implies wrt finishing off the population of a vector. Some operations might wish to use this to determine how much memory has been used by a vector so far, even though it is not finished being populated.

Specified by:

getBufferSizeFor in interface ValueVector

Parameters:

valueCount - the number of values to assume this vector contains

Returns:

the buffer size if this vector is holding valueCount values

getSizeFromCount

public static int getSizeFromCount(int valueCount)

getValueCapacity

public int getValueCapacity()

Description copied from interface: ValueVector

Returns the maximum number of values that can be stored in this vector instance.

Specified by:

getValueCapacity in interface ValueVector

setInitialCapacity

public void setInitialCapacity(int valueCount)

Description copied from interface: ValueVector

Set the initial record capacity

Specified by:

setInitialCapacity in interface ValueVector

allocateNew

public void allocateNew()

Description copied from interface: ValueVector

Allocate new buffers. ValueVector implements logic to determine how much to allocate.

Specified by:

allocateNew in interface ValueVector

allocateNewSafe

public boolean allocateNewSafe()

Description copied from interface: ValueVector

Allocates new buffers. ValueVector implements logic to determine how much to allocate.

Specified by:

allocateNewSafe in interface ValueVector

Returns:

Returns true if allocation was successful.

reset

public void reset()

Description copied from class: BaseDataValueVector

This method has a similar effect of allocateNew() without actually clearing and reallocating the value vector. The purpose is to move the value vector to a "mutate" state

Overrides:

reset in class BaseDataValueVector

allocateNew

public void allocateNew(int valueCount)

Allocate a new memory space for this vector. Must be called prior to using the ValueVector.

Specified by:

allocateNew in interface FixedWidthVector

Parameters:

valueCount - The number of values which can be contained within this vector.

reAlloc

public void reAlloc()

Allocate new buffer with double capacity, and copy data into the new buffer. Replace vector's buffer with new buffer, and release old one

reallocRaw

public DrillBuf reallocRaw(int newAllocationSize)

Description copied from class: BaseDataValueVector

Core of vector allocation. Given a new size (which must be a power of two), allocate the new buffer, copy the current values, and leave the unused parts garbage-filled.

Specified by:

reallocRaw in class BaseDataValueVector

Parameters:

newAllocationSize - new buffer size as a power of two

Returns:

the new buffer

zeroVector

public void zeroVector()

Zero out the underlying buffer backing this vector.

Specified by:

zeroVector in interface FixedWidthVector

getValueWidth

public int getValueWidth()

Description copied from interface: FixedWidthVector

The width of a record in bytes.

Specified by:

getValueWidth in interface FixedWidthVector

Returns:

The width of a record in bytes.

copyFrom

public void copyFrom(int inIndex,
                     int outIndex,
                     BitVector from)

copyFromSafe

public void copyFromSafe(int inIndex,
                         int outIndex,
                         BitVector from)

copyEntry

public void copyEntry(int toIndex,
                      ValueVector from,
                      int fromIndex)

Specified by:

copyEntry in interface ValueVector

load

public void load(UserBitShared.SerializedField metadata,
                 DrillBuf buffer)

Description copied from interface: ValueVector

Load the data provided in the buffer. Typically used when deserializing from the wire.

Specified by:

load in interface ValueVector

Parameters:

metadata - Metadata used to decode the incoming buffer.

buffer - The buffer that contains the ValueVector.

getMutator

public BitVector.Mutator getMutator()

Description copied from interface: ValueVector

Returns an mutator that is used to write to this vector instance.

Specified by:

getMutator in interface ValueVector

getAccessor

public BitVector.Accessor getAccessor()

Description copied from interface: ValueVector

Returns an accessor that is used to read from this vector instance.

Specified by:

getAccessor in interface ValueVector

getTransferPair

public TransferPair getTransferPair(BufferAllocator allocator)

Description copied from interface: ValueVector

Returns a transfer pair, creating a new target vector of the same type.

Specified by:

getTransferPair in interface ValueVector

Overrides:

getTransferPair in class BaseValueVector

getTransferPair

public TransferPair getTransferPair(String ref,
                                    BufferAllocator allocator)

Specified by:

getTransferPair in interface ValueVector

makeTransferPair

public TransferPair makeTransferPair(ValueVector to)

Description copied from interface: ValueVector

Returns a new transfer pair that is used to transfer underlying buffers into the target vector.

Specified by:

makeTransferPair in interface ValueVector

transferTo

public void transferTo(BitVector target)

splitAndTransferTo

public void splitAndTransferTo(int startIndex,
                               int length,
                               BitVector target)

exchange

public void exchange(ValueVector other)

Description copied from interface: ValueVector

Exchange state with another value vector of the same type. Used to implement look-ahead writers.

Specified by:

exchange in interface ValueVector

Overrides:

exchange in class BaseDataValueVector

clear

public void clear()

Description copied from interface: ValueVector

Release the underlying DrillBuf and reset the ValueVector to empty.

Specified by:

clear in interface ValueVector

Overrides:

clear in class BaseDataValueVector

getPayloadByteCount

public int getPayloadByteCount(int valueCount)

Description copied from interface: ValueVector

Return the number of value bytes consumed by actual data.

Specified by:

getPayloadByteCount in interface ValueVector

toNullable

public void toNullable(ValueVector nullableVector)

Description copied from interface: ValueVector

Convert a non-nullable vector to nullable by shuffling the data from one to the other. Avoids the need to generate copy code just to change mode. If this vector is non-nullable, accepts a nullable dual (same minor type, different mode.) If the vector is non-nullable, or non-scalar, then throws an exception.

Specified by:

toNullable in interface ValueVector

Overrides:

toNullable in class BaseValueVector

Parameters:

nullableVector - nullable vector of the same minor type as this vector