Package dev.failsafe.internal

Class RateLimiterImpl<R>

java.lang.Object

dev.failsafe.internal.RateLimiterImpl<R>

Type Parameters:

R - result type

All Implemented Interfaces:

Policy<R>, RateLimiter<R>

public class RateLimiterImpl<R>
extends Object
implements RateLimiter<R>

A RateLimiter implementation that supports smooth and bursty rate limiting.

Field Summary

Fields

Modifier and Type	Field	Description
private final RateLimiterConfig<R>	config
private final RateLimiterStats	stats

Constructor Summary

Constructors

Constructor	Description
RateLimiterImpl(RateLimiterConfig<R> config)
RateLimiterImpl(RateLimiterConfig<R> config, RateLimiterStats.Stopwatch stopwatch)

Method Summary

Modifier and Type	Method	Description
void	acquirePermits(int permits)	Attempts to acquire the requested permits to perform executions against the rate limiter, waiting until they are available or the thread is interrupted.
RateLimiterConfig<R>	getConfig()	Returns the RateLimiterConfig that the RateLimiter was built with.
Duration	reservePermits(int permits)	Reserves the permits to perform executions against the rate limiter, and returns the time that the caller is expected to wait before acting on the permits.
(package private) long	reservePermits(int permits, Duration maxWaitTime)
PolicyExecutor<R>	toExecutor(int policyIndex)	Returns a PolicyExecutor capable of handling an execution for the Policy.
boolean	tryAcquirePermits(int permits)	Tries to acquire the requested permits to perform executions against the rate limiter, returning immediately without waiting.
boolean	tryAcquirePermits(int permits, Duration maxWaitTime)	Tries to acquire the requested permits to perform executions against the rate limiter, waiting up to the maxWaitTime until they are available.
Duration	tryReservePermits(int permits, Duration maxWaitTime)	Tries to reserve the permits to perform executions against the rate limiter, and returns the time that the caller is expected to wait before acting on the permits, as long as it's less than the maxWaitTime.

Methods inherited from class java.lang.Object

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

Methods inherited from interface dev.failsafe.RateLimiter

acquirePermit, acquirePermit, acquirePermits, isBursty, isSmooth, reservePermit, tryAcquirePermit, tryAcquirePermit, tryReservePermit

Field Details

config

private final RateLimiterConfig<R> config

stats

private final RateLimiterStats stats

Constructor Details

RateLimiterImpl

public RateLimiterImpl(RateLimiterConfig<R> config)

RateLimiterImpl

RateLimiterImpl(RateLimiterConfig<R> config,
 RateLimiterStats.Stopwatch stopwatch)

Method Details

getConfig

public RateLimiterConfig<R> getConfig()

Description copied from interface: RateLimiter

Returns the RateLimiterConfig that the RateLimiter was built with.

Specified by:

getConfig in interface Policy<R>

Specified by:

getConfig in interface RateLimiter<R>

acquirePermits

public void acquirePermits(int permits)
                    throws InterruptedException

Description copied from interface: RateLimiter

Attempts to acquire the requested permits to perform executions against the rate limiter, waiting until they are available or the thread is interrupted.

Specified by:

acquirePermits in interface RateLimiter<R>

Throws:

InterruptedException - if the current thread is interrupted while waiting to acquire the permits

See Also:

• RateLimiter.tryAcquirePermits(int)
• RateLimiter.reservePermits(int)

reservePermits

public Duration reservePermits(int permits)

Description copied from interface: RateLimiter

Reserves the permits to perform executions against the rate limiter, and returns the time that the caller is expected to wait before acting on the permits. Returns 0 if the permits are immediately available and no waiting is needed.

Specified by:

reservePermits in interface RateLimiter<R>

See Also:

• RateLimiter.acquirePermits(int)
• RateLimiter.tryAcquirePermits(int)

tryAcquirePermits

public boolean tryAcquirePermits(int permits)

Description copied from interface: RateLimiter

Tries to acquire the requested permits to perform executions against the rate limiter, returning immediately without waiting.

Specified by:

tryAcquirePermits in interface RateLimiter<R>

Returns:

whether the requested permits are successfully acquired or not

See Also:

• RateLimiter.acquirePermits(int)

tryAcquirePermits

public boolean tryAcquirePermits(int permits,
 Duration maxWaitTime)
                          throws InterruptedException

Description copied from interface: RateLimiter

Tries to acquire the requested permits to perform executions against the rate limiter, waiting up to the maxWaitTime until they are available.

Specified by:

tryAcquirePermits in interface RateLimiter<R>

Returns:

whether the requested permits are successfully acquired or not

Throws:

InterruptedException - if the current thread is interrupted while waiting to acquire the permits

See Also:

• RateLimiter.acquirePermits(int, Duration)

tryReservePermits

public Duration tryReservePermits(int permits,
 Duration maxWaitTime)

Description copied from interface: RateLimiter

Tries to reserve the permits to perform executions against the rate limiter, and returns the time that the caller is expected to wait before acting on the permits, as long as it's less than the maxWaitTime.

• Returns the expected wait time for the permits if they were successfully reserved.
• Returns 0 if the permits were successfully reserved and no waiting is needed.
• Returns -1 nanoseconds if the permits were not reserved because the wait time would be greater than the maxWaitTime.

Specified by:

tryReservePermits in interface RateLimiter<R>

See Also:

• RateLimiter.acquirePermit(Duration)
• RateLimiter.tryAcquirePermit(Duration)

toExecutor

public PolicyExecutor<R> toExecutor(int policyIndex)

Description copied from interface: Policy

Returns a PolicyExecutor capable of handling an execution for the Policy.

Specified by:

toExecutor in interface Policy<R>

reservePermits

long reservePermits(int permits,
 Duration maxWaitTime)