org.isomorphism.util

Class FixedIntervalRefillStrategy

java.lang.Object

org.isomorphism.util.FixedIntervalRefillStrategy

All Implemented Interfaces:

TokenBucket.RefillStrategy

public class FixedIntervalRefillStrategy
extends Object
implements TokenBucket.RefillStrategy

A token bucket refill strategy that will provide N tokens for a token bucket to consume every T units of time. The tokens are refilled in bursts rather than at a fixed rate. This refill strategy will never allow more than N tokens to be consumed during a window of time T.

Constructor Summary

Constructors

Constructor and Description
FixedIntervalRefillStrategy(com.google.common.base.Ticker ticker, long numTokensPerPeriod, long period, TimeUnit unit) Create a FixedIntervalRefillStrategy.

Method Summary

Modifier and Type	Method and Description
long	getDurationUntilNextRefill(TimeUnit unit) Returns the amount of time in the specified time unit until the next group of tokens can be added to the token bucket.
long	refill() Returns the number of tokens to add to the token bucket.

Methods inherited from class java.lang.Object

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

Constructor Detail

FixedIntervalRefillStrategy

public FixedIntervalRefillStrategy(com.google.common.base.Ticker ticker,
                                   long numTokensPerPeriod,
                                   long period,
                                   TimeUnit unit)

Create a FixedIntervalRefillStrategy.

Parameters:

ticker - A ticker to use to measure time.

numTokensPerPeriod - The number of tokens to add to the bucket every period.

period - How often to refill the bucket.

unit - Unit for period.

Method Detail

refill

public long refill()

Description copied from interface: TokenBucket.RefillStrategy

Returns the number of tokens to add to the token bucket.

Specified by:

refill in interface TokenBucket.RefillStrategy

Returns:

The number of tokens to add to the token bucket.

getDurationUntilNextRefill

public long getDurationUntilNextRefill(TimeUnit unit)

Description copied from interface: TokenBucket.RefillStrategy

Returns the amount of time in the specified time unit until the next group of tokens can be added to the token bucket. Please note, depending on the SleepStrategy used by the token bucket, tokens may not actually be added until much after the returned duration. If for some reason the implementation of RefillStrategy doesn't support knowing when the next batch of tokens will be added, then an UnsupportedOperationException may be thrown. Lastly, if the duration until the next time tokens will be added to the token bucket is less than a single unit of the passed in time unit then this method will return 0.

Specified by:

getDurationUntilNextRefill in interface TokenBucket.RefillStrategy

Parameters:

unit - The time unit to express the return value in.

Returns:

The amount of time until the next group of tokens can be added to the token bucket.