Package org.apache.kafka.common.metrics

Class Sensor

java.lang.Object
org.apache.kafka.common.metrics.Sensor
public final class Sensor extends Object
A sensor applies a continuous sequence of numerical values to a set of associated metrics. For example a sensor on message size would record a sequence of message sizes using the record(double) api and would maintain a set of metrics about request sizes such as the average or max.

  • Method Details

    • name

      public String name()
      The name this sensor is registered with. This name will be unique among all registered sensors.

    • shouldRecord

      public boolean shouldRecord()
      Returns:
      true if the sensor's record level indicates that the metric will be recorded, false otherwise

    • record

      public void record()
      Record an occurrence, this is just short-hand for record(1.0)

    • record

      public void record(double value)
      Record a value with this sensor
      Parameters:
      value - The value to record
      Throws:
      QuotaViolationException - if recording this value moves a metric beyond its configured maximum or minimum bound

    • record

      public void record(double value, long timeMs)
      Record a value at a known time. This method is slightly faster than record(double) since it will reuse the time stamp.
      Parameters:
      value - The value we are recording
      timeMs - The current POSIX time in milliseconds
      Throws:
      QuotaViolationException - if recording this value moves a metric beyond its configured maximum or minimum bound

    • record

      public void record(double value, long timeMs, boolean checkQuotas)
      Record a value at a known time. This method is slightly faster than record(double) since it will reuse the time stamp.
      Parameters:
      value - The value we are recording
      timeMs - The current POSIX time in milliseconds
      checkQuotas - Indicate if quota must be enforced or not
      Throws:
      QuotaViolationException - if recording this value moves a metric beyond its configured maximum or minimum bound

    • checkQuotas

      public void checkQuotas()
      Check if we have violated our quota for any metric that has a configured quota

    • checkQuotas

      public void checkQuotas(long timeMs)

    • add

      public boolean add(CompoundStat stat)
      Register a compound statistic with this sensor with no config override
      Parameters:
      stat - The stat to register
      Returns:
      true if stat is added to sensor, false if sensor is expired

    • add

      public boolean add(CompoundStat stat, MetricConfig config)
      Register a compound statistic with this sensor which yields multiple measurable quantities (like a histogram)
      Parameters:
      stat - The stat to register
      config - The configuration for this stat. If null then the stat will use the default configuration for this sensor.
      Returns:
      true if stat is added to sensor, false if sensor is expired

    • add

      public boolean add(MetricName metricName, MeasurableStat stat)
      Register a metric with this sensor
      Parameters:
      metricName - The name of the metric
      stat - The statistic to keep
      Returns:
      true if metric is added to sensor, false if sensor is expired

    • add

      public boolean add(MetricName metricName, MeasurableStat stat, MetricConfig config)
      Register a metric with this sensor
      Parameters:
      metricName - The name of the metric
      stat - The statistic to keep
      config - A special configuration for this metric. If null use the sensor default configuration.
      Returns:
      true if metric is added to sensor, false if sensor is expired

    • hasMetrics

      public boolean hasMetrics()
      Return if metrics were registered with this sensor.
      Returns:
      true if metrics were registered, false otherwise

    • hasExpired

      public boolean hasExpired()
      Return true if the Sensor is eligible for removal due to inactivity. false otherwise