org.red5.server.stream
Interface ITokenBucket

public interface ITokenBucket

Basically token bucket is used to control the bandwidth used by a stream or a connection or a client. There's a background thread that distributes tokens to the buckets in the system according to the configuration of the bucket. The configuration includes how fast the tokens are distributed. When a stream, for example, needs to send out a packet, the packet's byte count is calculated and each byte corresponds to a token in the bucket. The stream is assigned a bucket and the tokens in the bucket are acquired before the packet can be sent out. So if the speed(or bandwidth) in configuration is low, the stream can't send out packets fast.

Author:

The Red5 Project ([email protected]), Steven Gong ([email protected])

Nested Class Summary

static interface

ITokenBucket.ITokenBucketCallback Callback for tocket bucket

Method Summary

boolean	acquireToken(long tokenCount, long wait) Acquire tokens amount of tokenCount waiting wait milliseconds if token not available.
long	acquireTokenBestEffort(long upperLimitCount) Nonblockingly acquire token.
boolean	acquireTokenNonblocking(long tokenCount, ITokenBucket.ITokenBucketCallback callback) Nonblockingly acquire token.
long	getCapacity() Get the capacity of this bucket in Byte.
double	getSpeed() The amount of tokens increased per millisecond.
void	reset() Reset this token bucket.

Method Detail

acquireToken

boolean acquireToken(long tokenCount,
                     long wait)

Acquire tokens amount of tokenCount waiting wait milliseconds if token not available.

Parameters:

tokenCount - The count of tokens to acquire.

wait - Milliseconds to wait. 0 means no wait and any value below zero means wait forever.

Returns:

true if successfully acquired or false if not acquired.

acquireTokenNonblocking

boolean acquireTokenNonblocking(long tokenCount,
                                ITokenBucket.ITokenBucketCallback callback)

Nonblockingly acquire token. If the token is not available and task is not null, the callback will be executed when the token is available. The tokens are not consumed automatically before callback, so it's recommended to acquire token again in callback function.

Parameters:

tokenCount - Number of tokens

callback - Callback

Returns:

true if successfully acquired or false if not acquired.

acquireTokenBestEffort

long acquireTokenBestEffort(long upperLimitCount)

Nonblockingly acquire token. The upper limit is specified. If not enough tokens are left in bucket, all remaining will be returned.

Parameters:

upperLimitCount - Upper limit of aquisition

Returns:

Remaining tokens from bucket

getCapacity

long getCapacity()

Get the capacity of this bucket in Byte.

Returns:

Capacity of this bucket in bytes

getSpeed

double getSpeed()

The amount of tokens increased per millisecond.

Returns:

Amount of tokens increased per millisecond.

reset

void reset()

Reset this token bucket. All pending threads are woken up with false returned for acquiring token and callback is removed without calling back.