FixedSizeSlidingWindowMetrics (resilience4j-core 1.6.0 API)

java.lang.Object
- io.github.resilience4j.core.metrics.FixedSizeSlidingWindowMetrics

All Implemented Interfaces:

Metrics
```
public class FixedSizeSlidingWindowMetrics
extends java.lang.Object
implements Metrics
```
A Metrics implementation is backed by a sliding window that aggregates only the last N calls.
The sliding window is implemented with a circular array of N measurements. If the time window size is 10, the circular array has always 10 measurements.
The sliding window incrementally updates a total aggregation. The total aggregation is updated incrementally when a new call outcome is recorded. When the oldest measurement is evicted, the measurement is subtracted from the total aggregation. (Subtract-on-Evict)
The time to retrieve a Snapshot is constant 0(1), since the Snapshot is pre-aggregated and is independent of the window size. The space requirement (memory consumption) of this implementation should be O(n).

Nested Class Summary
- Nested classes/interfaces inherited from interface io.github.resilience4j.core.metrics.Metrics
  Metrics.Outcome

Constructor Summary

Constructors
Constructor Description

FixedSizeSlidingWindowMetrics(int windowSize)
Creates a new FixedSizeSlidingWindowMetrics with the given window size.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`Snapshot`	`getSnapshot()`	Returns a snapshot.
`Snapshot`	`record(long duration, java.util.concurrent.TimeUnit durationUnit, Metrics.Outcome outcome)`	Records a call.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - FixedSizeSlidingWindowMetrics
```
public FixedSizeSlidingWindowMetrics(int windowSize)
```
    Creates a new FixedSizeSlidingWindowMetrics with the given window size.
    
    Parameters:
    
    windowSize - the window size
- Method Detail
  - record
```
public Snapshot record(long duration,
                       java.util.concurrent.TimeUnit durationUnit,
                       Metrics.Outcome outcome)
```
    Description copied from interface: Metrics
    
    Records a call.
    
    Specified by:
    
    record in interface Metrics
    
    Parameters:
    
    duration - the duration of the call
    
    durationUnit - the time unit of the duration
    
    outcome - the outcome of the call
  - getSnapshot
```
public Snapshot getSnapshot()
```
    Description copied from interface: Metrics
    
    Returns a snapshot.
    
    Specified by:
    
    getSnapshot in interface Metrics
    
    Returns:
    
    a snapshot