```
@Inherited
@Retention(RUNTIME)
@Documented
@InterceptorBinding
@Target({METHOD,TYPE})
@Experimental("first attempt at providing rate limit")
public @interface RateLimit
```
Rate limit restricts the number of invocations in a time window of some length. An invocation is permitted when the number of recent invocations is below the configured limit. An invocation that would cause the number of recent invocations to exceed the limit is rejected with RateLimitException.
What "recent" means differs based on the type of the time windows configured. By default, the time windows are fixed, which means that time is divided into a series of consecutive intervals of given length (time windows) and the limit is compared against the number of invocations in the current window. Two different time windows may be configured. With rolling time windows, each invocation has its own time window of given length, overlapping with time windows of previous invocations. This is more precise but requires more memory and may be slower. Using smooth time windows means that invocations are uniformly distributed over time under a calculated rate.
Additionally, a minimum spacing of invocations may be configured. If set, an invocation that happens too quickly after a previous invocation is always rejected with RateLimitException, even if the limit has not been exceeded yet.
With fixed and rolling time windows, rejected invocations always count towards the limit, so if a caller continuously invokes the guarded method faster than the configuration allows, all invocations are rejected until the caller slows down. With smooth time windows, rejected invocations do not count towards the recent rate of invocations.

See Also:

value(), window(), windowUnit(), minSpacing(), minSpacingUnit(), type()

Optional Element Summary

Optional Elements
Modifier and Type	Optional Element	Description
`long`	`minSpacing`	Minimum time between two consecutive invocations.
`ChronoUnit`	`minSpacingUnit`	The unit of the minimum time between two consecutive invocations.
`RateLimitType`	`type`	Type of time windows used for rate limiting.
`int`	`value`	Maximum number of invocations in a time window.
`long`	`window`	The time window length.
`ChronoUnit`	`windowUnit`	The unit of length of a time window.

- Element Detail
  - value
```
int value
```
    Maximum number of invocations in a time window.
    Value must be greater than 0.
    
    Returns:
    
    maximum number of invocations in a time window
    
    See Also:
    
    window()
    
    Default:
    
    100
- - window
```
long window
```
    The time window length.
    Value must be greater than 0.
    
    Returns:
    
    the time window length
    
    See Also:
    
    value(), windowUnit()
    
    Default:
    
    1L
- - windowUnit
```
ChronoUnit windowUnit
```
    The unit of length of a time window.
    
    Returns:
    
    the unit of length
    
    See Also:
    
    window()
    
    Default:
    
    java.time.temporal.ChronoUnit.SECONDS
- - minSpacing
```
long minSpacing
```
    Minimum time between two consecutive invocations. If the time between two consecutive invocations is shorter, the second invocation is rejected.
    Value must be greater than or equal to 0. When 0, the minimum time check is effectively disabled.
    
    Returns:
    
    minimum time between two consecutive invocations
    
    See Also:
    
    minSpacingUnit()
    
    Default:
    
    0L
- - minSpacingUnit
```
ChronoUnit minSpacingUnit
```
    The unit of the minimum time between two consecutive invocations.
    
    Returns:
    
    the unit of minimum time
    
    See Also:
    
    minSpacing()
    
    Default:
    
    java.time.temporal.ChronoUnit.SECONDS
- - type
```
RateLimitType type
```
    Type of time windows used for rate limiting.
    
    Returns:
    
    the time window type
    
    See Also:
    
    RateLimitType
    
    Default:
    
    io.smallrye.faulttolerance.api.RateLimitType.FIXED

Annotation Type RateLimit

Optional Element Summary

Element Detail

value

window

windowUnit

minSpacing

minSpacingUnit

type