com.amazonaws.util

Class CapacityManager

java.lang.Object

com.amazonaws.util.CapacityManager

public class CapacityManager
extends Object

Manages capacity of a finite resource. Capacity can be acquired and released.

Constructor Summary

Constructors

Constructor and Description
CapacityManager(int maxCapacity) Creates a CapacityManager.

Method Summary

Modifier and Type	Method and Description
boolean	acquire() Attempts to acquire a single capacity unit.
boolean	acquire(int capacity) Attempts to acquire a given amount of capacity.
int	availableCapacity() Returns the currently available capacity.
int	consumedCapacity() Returns the currently consumed capacity.
void	release() Releases a single unit of capacity back to the pool, making it available to consumers.
void	release(int capacity) Releases a given amount of capacity back to the pool, making it available to consumers.

Methods inherited from class java.lang.Object

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

Constructor Detail

CapacityManager

public CapacityManager(int maxCapacity)

Creates a CapacityManager.

Parameters:

maxCapacity - maximum capacity of this resource. available capacity will initially be set to this value. if a negative value is provided the capacity manager will operate in a no-op passthrough mode in which all acquire calls will return true.

Method Detail

acquire

public boolean acquire()

Attempts to acquire a single capacity unit. If acquired, capacity will be consumed from the available pool.

Returns:

true if capacity can be acquired, false if not

acquire

public boolean acquire(int capacity)

Attempts to acquire a given amount of capacity. If acquired, capacity will be consumed from the available pool.

Parameters:

capacity - capacity to acquire

Returns:

true if capacity can be acquired, false if not

Throws:

IllegalArgumentException - if given capacity is negative

release

public void release()

Releases a single unit of capacity back to the pool, making it available to consumers.

release

public void release(int capacity)

Releases a given amount of capacity back to the pool, making it available to consumers.

Parameters:

capacity - capacity to release

Throws:

IllegalArgumentException - if given capacity is negative

consumedCapacity

public int consumedCapacity()

Returns the currently consumed capacity.

Returns:

consumed capacity

availableCapacity

public int availableCapacity()

Returns the currently available capacity.

Returns:

available capacity