org.apache.drill.exec.memory

Class BaseAllocator.Reservation

java.lang.Object

org.apache.drill.exec.memory.BaseAllocator.Reservation

All Implemented Interfaces:

AutoCloseable, AllocationReservation

Enclosing class:

BaseAllocator

public class BaseAllocator.Reservation
extends Object
implements AllocationReservation

Constructor Summary

Constructors

Constructor and Description
Reservation()

Method Summary

Modifier and Type	Method and Description
boolean	add(int nBytes) Add to the current reservation.
DrillBuf	allocateBuffer() Allocate a buffer whose size is the total of all the add()s made.
void	close()
int	getSize() Get the current size of the reservation (the sum of all the add()s).
boolean	isClosed() Return whether or not the reservation has been closed.
boolean	isUsed() Return whether or not the reservation has been used.
boolean	reserve(int nBytes) Requests a reservation of additional space.

Methods inherited from class java.lang.Object

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

Constructor Detail

Reservation

public Reservation()

Method Detail

add

public boolean add(int nBytes)

Description copied from interface: AllocationReservation

Add to the current reservation.

Adding may fail if the allocator is not allowed to consume any more space.

Specified by:

add in interface AllocationReservation

Parameters:

nBytes - the number of bytes to add

Returns:

true if the addition is possible, false otherwise

allocateBuffer

public DrillBuf allocateBuffer()

Description copied from interface: AllocationReservation

Allocate a buffer whose size is the total of all the add()s made.

The allocation request can still fail, even if the amount of space requested is available, if the allocation cannot be made contiguously.

Specified by:

allocateBuffer in interface AllocationReservation

Returns:

the buffer, or null, if the request cannot be satisfied

getSize

public int getSize()

Description copied from interface: AllocationReservation

Get the current size of the reservation (the sum of all the add()s).

Specified by:

getSize in interface AllocationReservation

Returns:

size of the current reservation

isUsed

public boolean isUsed()

Description copied from interface: AllocationReservation

Return whether or not the reservation has been used.

Specified by:

isUsed in interface AllocationReservation

Returns:

whether or not the reservation has been used

isClosed

public boolean isClosed()

Description copied from interface: AllocationReservation

Return whether or not the reservation has been closed.

Specified by:

isClosed in interface AllocationReservation

Returns:

whether or not the reservation has been closed

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface AllocationReservation

reserve

public boolean reserve(int nBytes)

Description copied from interface: AllocationReservation

Requests a reservation of additional space.

The implementation of the allocator's inner class provides this.

Specified by:

reserve in interface AllocationReservation

Parameters:

nBytes - the amount to reserve

Returns:

true if the reservation can be satisfied, false otherwise