Package org.apache.arrow.vector

Class AllocationHelper

java.lang.Object

org.apache.arrow.vector.AllocationHelper

public class AllocationHelper
extends Object

Helper utility methods for allocating storage for Vectors.

Method Summary

Modifier and Type	Method	Description
static void	allocate(ValueVector v, int valueCount, int bytesPerValue)	Allocates the vector.
static void	allocate(ValueVector v, int valueCount, int bytesPerValue, int repeatedPerTop)	Allocates memory for a vector assuming given number of values and their width.
static void	allocateNew(ValueVector v, int valueCount)	Allocates the exact amount if v is fixed width, otherwise falls back to dynamic allocation.
static void	allocatePrecomputedChildCount(ValueVector v, int valueCount, int bytesPerValue, int childValCount)	Allocates memory for a vector assuming given number of values and their width.

Methods inherited from class java.lang.Object

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

Method Details

allocate

public static void allocate(ValueVector v,
 int valueCount,
 int bytesPerValue)

Allocates the vector.

Parameters:

v - The vector to allocate.

valueCount - Number of values to allocate.

bytesPerValue - bytes per value.

Throws:

OutOfMemoryException - if it can't allocate the memory.

allocatePrecomputedChildCount

public static void allocatePrecomputedChildCount(ValueVector v,
 int valueCount,
 int bytesPerValue,
 int childValCount)

Allocates memory for a vector assuming given number of values and their width.

Parameters:

v - The vector the allocate.

valueCount - The number of elements to allocate.

bytesPerValue - The bytes per value to use for allocating underlying storage

childValCount - If v is a repeated vector, this is number of child elements to allocate.

Throws:

OutOfMemoryException - if it can't allocate the memory.

allocate

public static void allocate(ValueVector v,
 int valueCount,
 int bytesPerValue,
 int repeatedPerTop)

Allocates memory for a vector assuming given number of values and their width.

Parameters:

v - The vector the allocate.

valueCount - The number of elements to allocate.

bytesPerValue - The bytes per value to use for allocating underlying storage

repeatedPerTop - If v is a repeated vector, this is assumed number of elements per child.

Throws:

OutOfMemoryException - if it can't allocate the memory

allocateNew

public static void allocateNew(ValueVector v,
 int valueCount)

Allocates the exact amount if v is fixed width, otherwise falls back to dynamic allocation.

Parameters:

v - value vector we are trying to allocate

valueCount - size we are trying to allocate

Throws:

OutOfMemoryException - if it can't allocate the memory