org.apache.hadoop.hive.common.io

Interface Allocator

public interface Allocator

An allocator provided externally to storage classes to allocate MemoryBuffer-s.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	Allocator.AllocatorOutOfMemoryException

Method Summary

Modifier and Type	Method and Description
void	allocateMultiple(MemoryBuffer[] dest, int size) Allocates multiple buffers of a given size.
MemoryBuffer	createUnallocated() Creates an unallocated memory buffer object.
void	deallocate(MemoryBuffer buffer) Deallocates a memory buffer.
int	getMaxAllocation() Maximum allocation size supported by this allocator.
boolean	isDirectAlloc() Whether the allocator uses direct buffers.

Method Detail

allocateMultiple

void allocateMultiple(MemoryBuffer[] dest,
                      int size)
               throws Allocator.AllocatorOutOfMemoryException

Allocates multiple buffers of a given size.

Parameters:

dest - Array where buffers are placed. Objects are reused if already there (see createUnallocated), created otherwise.

size - Allocation size.

Throws:

Allocator.AllocatorOutOfMemoryException - Cannot allocate.

createUnallocated

MemoryBuffer createUnallocated()

Creates an unallocated memory buffer object. This object can be passed to allocateMultiple to allocate; this is useful if data structures are created for separate buffers that can later be allocated together.

deallocate

void deallocate(MemoryBuffer buffer)

Deallocates a memory buffer.

isDirectAlloc

boolean isDirectAlloc()

Whether the allocator uses direct buffers.

getMaxAllocation

int getMaxAllocation()

Maximum allocation size supported by this allocator.