Trait SampledStatKind 

pub trait SampledStatKind: Send + Sync {
    // Required methods
    fn update(
        &self,
        sample: &mut Sample,
        config: &MetricConfig,
        value: f64,
        time_ms: i64,
    );
    fn combine(
        &self,
        samples: &[Sample],
        config: &MetricConfig,
        now: i64,
    ) -> f64;

    // Provided methods
    fn is_windowed_count(&self) -> bool { ... }
    fn is_windowed_sum(&self) -> bool { ... }
}

The per-subclass behaviour of a SampledStat.

Java’s SampledStat is abstract with update/combine provided by each subclass and an initialValue passed to the constructor. We model those abstract methods as this trait object held by the concrete SampledStat struct, plus the initial_value stored on the struct. newSample is NOT virtual in Java, so it stays on SampledStat itself.

Required Methods

fn update( &self, sample: &mut Sample, config: &MetricConfig, value: f64, time_ms: i64, )

Update the current sample with the recorded value (Java update).

fn combine(&self, samples: &[Sample], config: &MetricConfig, now: i64) -> f64

Combine all samples into a single measurement (Java combine).

Provided Methods

fn is_windowed_count(&self) -> bool

Whether this is a WindowedCount (counts invocations rather than summing values). Used by crate::common::metrics::stats::Meter to decide whether the total records 1.0, mirroring Java’s rate.stat instanceof WindowedCount check. Defaults to false; only WindowedCount overrides it.

fn is_windowed_sum(&self) -> bool

Whether this is a WindowedSum (or a subclass of it). Meter only supports a WindowedSum/WindowedCount rate stat, mirroring Java’s instanceof WindowedSum guard. Defaults to false.

Implementors