Package org.apache.cassandra.utils.concurrent

Class NonBlockingRateLimiter

java.lang.Object

org.apache.cassandra.utils.concurrent.NonBlockingRateLimiter

@ThreadSafe
public class NonBlockingRateLimiter
extends Object

A rate limiter implementation that allows callers to reserve permits that may only be available in the future, delegating to them decisions about how to schedule/delay work and whether or not to block execution to do so.

Field Summary

Fields

Modifier and Type	Field	Description
static final long	NANOS_PER_SECOND
static final NonBlockingRateLimiter	NO_OP_LIMITER

Constructor Summary

Constructors

Constructor	Description
NonBlockingRateLimiter(int permitsPerSecond)
NonBlockingRateLimiter(int permitsPerSecond, long burstNanos, com.google.common.base.Ticker ticker)

Method Summary

Modifier and Type	Method	Description
long	getIntervalNanos()
int	getRate()
long	getStartedNanos()
long	reserveAndGetDelay(TimeUnit delayUnit)	Reserves a single permit slot on the timeline which may not yet be available.
void	setRate(int permitsPerSecond)
void	setRate(int permitsPerSecond, com.google.common.base.Ticker ticker)
boolean	tryReserve()	Reserves a single permit slot on the timeline, but only if one is available.

Methods inherited from class java.lang.Object

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

Field Details

NANOS_PER_SECOND

public static final long NANOS_PER_SECOND

NO_OP_LIMITER

public static final NonBlockingRateLimiter NO_OP_LIMITER

Constructor Details

NonBlockingRateLimiter

public NonBlockingRateLimiter(int permitsPerSecond)

NonBlockingRateLimiter

public NonBlockingRateLimiter(int permitsPerSecond,
 long burstNanos,
 com.google.common.base.Ticker ticker)

Method Details

setRate

public void setRate(int permitsPerSecond)

setRate

public void setRate(int permitsPerSecond,
 com.google.common.base.Ticker ticker)

getRate

public int getRate()

Returns:

the number of available permits per second

reserveAndGetDelay

public long reserveAndGetDelay(TimeUnit delayUnit)

Reserves a single permit slot on the timeline which may not yet be available.

Returns:

time until the reserved permit will be available (or zero if it already is) in the specified units

tryReserve

public boolean tryReserve()

Reserves a single permit slot on the timeline, but only if one is available.

Returns:

true if a permit is available, false if one is not

getIntervalNanos

public long getIntervalNanos()

getStartedNanos

public long getStartedNanos()