Package io.github.resilience4j.ratelimiter.internal

Class AtomicRateLimiter

java.lang.Object

io.github.resilience4j.ratelimiter.internal.AtomicRateLimiter

All Implemented Interfaces:

RateLimiter

public class AtomicRateLimiter
extends java.lang.Object
implements RateLimiter

AtomicRateLimiter splits all nanoseconds from the start of epoch into cycles.

Each cycle has duration of RateLimiterConfig.limitRefreshPeriod in nanoseconds.

By contract on start of each cycle AtomicRateLimiter should set AtomicRateLimiter.State.activePermissions to RateLimiterConfig.limitForPeriod. For the AtomicRateLimiter callers it is really looks so, but under the hood there is some optimisations that will skip this refresh if AtomicRateLimiter is not used actively.

All AtomicRateLimiter updates are atomic and state is encapsulated in AtomicReference to AtomicRateLimiter.State

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	AtomicRateLimiter.AtomicRateLimiterMetrics	Enhanced RateLimiter.Metrics with some implementation specific details

Nested classes/interfaces inherited from interface io.github.resilience4j.ratelimiter.RateLimiter

RateLimiter.EventPublisher, RateLimiter.Metrics

Constructor Summary

Constructors

Constructor	Description
AtomicRateLimiter(java.lang.String name, RateLimiterConfig rateLimiterConfig)
AtomicRateLimiter(java.lang.String name, RateLimiterConfig rateLimiterConfig, io.vavr.collection.Map<java.lang.String,java.lang.String> tags)

Method Summary

Modifier and Type	Method	Description
boolean	acquirePermission(int permits)	Acquires the given number of permits from this rate limiter, blocking until one is available, or the thread is interrupted.
void	changeLimitForPeriod(int limitForPeriod)	Dynamic rate limiter configuration change.
void	changeTimeoutDuration(java.time.Duration timeoutDuration)	Dynamic rate limiter configuration change.
AtomicRateLimiter.AtomicRateLimiterMetrics	getDetailedMetrics()	Get the enhanced Metrics with some implementation specific details.
RateLimiter.EventPublisher	getEventPublisher()	Returns an EventPublisher which can be used to register event consumers.
RateLimiter.Metrics	getMetrics()	Get the Metrics of this RateLimiter.
java.lang.String	getName()	Get the name of this RateLimiter
RateLimiterConfig	getRateLimiterConfig()	Get the RateLimiterConfig of this RateLimiter.
io.vavr.collection.Map<java.lang.String,java.lang.String>	getTags()	Returns an unmodifiable map with tags assigned to this RateLimiter.
long	reservePermission(int permits)	Reserves the given number permits from this rate limiter and returns nanoseconds you should wait for it.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.github.resilience4j.ratelimiter.RateLimiter

acquirePermission, executeCallable, executeCallable, executeCheckedSupplier, executeCheckedSupplier, executeCompletionStage, executeEitherSupplier, executeEitherSupplier, executeRunnable, executeRunnable, executeSupplier, executeSupplier, executeTrySupplier, executeTrySupplier, reservePermission

Constructor Detail

AtomicRateLimiter

public AtomicRateLimiter(java.lang.String name,
                         RateLimiterConfig rateLimiterConfig)

AtomicRateLimiter

public AtomicRateLimiter(java.lang.String name,
                         RateLimiterConfig rateLimiterConfig,
                         io.vavr.collection.Map<java.lang.String,java.lang.String> tags)

Method Detail

changeTimeoutDuration

public void changeTimeoutDuration(java.time.Duration timeoutDuration)

Dynamic rate limiter configuration change. This method allows to change timeout duration of current limiter. NOTE! New timeout duration won't affect threads that are currently waiting for permission.

Specified by:

changeTimeoutDuration in interface RateLimiter

Parameters:

timeoutDuration - new timeout duration

changeLimitForPeriod

public void changeLimitForPeriod(int limitForPeriod)

Dynamic rate limiter configuration change. This method allows to change count of permissions available during refresh period. NOTE! New limit won't affect current period permissions and will apply only from next one.

Specified by:

changeLimitForPeriod in interface RateLimiter

Parameters:

limitForPeriod - new permissions limit

acquirePermission

public boolean acquirePermission(int permits)

Acquires the given number of permits from this rate limiter, blocking until one is available, or the thread is interrupted. Maximum wait time is RateLimiterConfig.getTimeoutDuration()

If the current thread is interrupted while waiting for a permit then it won't throw InterruptedException, but its interrupt status will be set.

Specified by:

acquirePermission in interface RateLimiter

Parameters:

permits - number of permits - use for systems where 1 call != 1 permit

Returns:

true if a permit was acquired and false if waiting timeoutDuration elapsed before a permit was acquired

reservePermission

public long reservePermission(int permits)

Reserves the given number permits from this rate limiter and returns nanoseconds you should wait for it. If returned long is negative, it means that you failed to reserve permission, possibly your RateLimiterConfig.getTimeoutDuration() is less then time to wait for permission.

Specified by:

reservePermission in interface RateLimiter

Parameters:

permits - number of permits - use for systems where 1 call != 1 permit

Returns:

long amount of nanoseconds you should wait for reserved permissions. if negative, it means you failed to reserve.

getName

public java.lang.String getName()

Get the name of this RateLimiter

Specified by:

getName in interface RateLimiter

Returns:

the name of this RateLimiter

getRateLimiterConfig

public RateLimiterConfig getRateLimiterConfig()

Get the RateLimiterConfig of this RateLimiter.

Specified by:

getRateLimiterConfig in interface RateLimiter

Returns:

the RateLimiterConfig of this RateLimiter

getTags

public io.vavr.collection.Map<java.lang.String,java.lang.String> getTags()

Returns an unmodifiable map with tags assigned to this RateLimiter.

Specified by:

getTags in interface RateLimiter

Returns:

the tags assigned to this Retry in an unmodifiable map

getMetrics

public RateLimiter.Metrics getMetrics()

Get the Metrics of this RateLimiter.

Specified by:

getMetrics in interface RateLimiter

Returns:

the Metrics of this RateLimiter

getEventPublisher

public RateLimiter.EventPublisher getEventPublisher()

Description copied from interface: RateLimiter

Returns an EventPublisher which can be used to register event consumers.

Specified by:

getEventPublisher in interface RateLimiter

Returns:

an EventPublisher

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getDetailedMetrics

public AtomicRateLimiter.AtomicRateLimiterMetrics getDetailedMetrics()

Get the enhanced Metrics with some implementation specific details.

Returns:

the detailed metrics