akka.util

Class TokenBucket

java.lang.Object

akka.util.TokenBucket

Direct Known Subclasses:

NanoTimeTokenBucket

public abstract class TokenBucket
extends java.lang.Object

INTERNAL API

Constructor Summary

Constructors

Constructor and Description
TokenBucket(long capacity, long nanosBetweenTokens)

Method Summary

Modifier and Type	Method and Description
abstract long	currentTime() The current time in nanos.
void	init() This method must be called before the token bucket can be used.
long	offer(long cost) Call this (side-effecting) method whenever an element should be passed through the token-bucket.

Methods inherited from class java.lang.Object

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

Constructor Detail

TokenBucket

public TokenBucket(long capacity,
                   long nanosBetweenTokens)

Method Detail

init

public void init()

This method must be called before the token bucket can be used.

currentTime

public abstract long currentTime()

The current time in nanos. The returned value is monotonic, might wrap over and has no relationship with wall-clock.

Returns:

return the current time in nanos as a Long.

offer

public long offer(long cost)

Call this (side-effecting) method whenever an element should be passed through the token-bucket. This method will return the number of nanoseconds the element needs to be delayed to conform with the token bucket parameters. Returns zero if the element can be emitted immediately. The method does not handle overflow, if an element is to be delayed longer in nanoseconds than what can be represented as a positive Long then an undefined value is returned.

If a non-zero value is returned, it is the responsibility of the caller to not call this method before the returned delay has been elapsed (but can be called later). This class does not check or protect against early calls.

Parameters:

cost - How many tokens the element costs. Can be larger than the capacity of the bucket.

Returns: