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.getLimitRefreshPeriod() in nanoseconds.

By contract on start of each cycle AtomicRateLimiter should set AtomicRateLimiter.State.activePermissions to RateLimiterConfig.getLimitForPeriod(). 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

  • Constructor Details

  • Method Details

    • 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.

    • drainPermissions

      public void drainPermissions()
      Description copied from interface: RateLimiter
      Drains all the permits left in the current period.
      Specified by:
      drainPermissions in interface RateLimiter

    • 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