APIObservableCounter<T extends num> class

APIObservableCounter is an asynchronous Instrument which reports monotonically increasing value(s) when the instrument is being observed.

An ObservableCounter is intended for capturing values that can only increase, such as the system uptime, the number of total bytes received, or the number of page faults.

Constructors

APIObservableCounter.new(String _name, String? _description, String? _unit, bool _enabled, APIMeter _meter, ObservableCallback<T>? callback)
Creates a new observable counter instrument

Properties

callbacks List<ObservableCallback<T>>
Returns the current list of callbacks registered to this instrument.
no setter
description String?
Returns the description of this observable counter.
no setter
enabled bool
Returns whether this observable counter is enabled.
no setter
hashCode int
The hash code for this object.
no setterinherited
meter APIMeter
Returns the meter that created this observable counter.
no setter
name String
Returns the name of this observable counter.
no setter
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
unit String?
Returns the unit of this observable counter.
no setter

Methods

addCallback(ObservableCallback<T> callback) APICallbackRegistration<T>
Registers a callback function that will be invoked when the instrument is observed.
collect() List<Measurement<num>>
Collects measurements from all registered callbacks. This method is typically only called by the SDK during collection.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
removeCallback(ObservableCallback<T> callback) → void
Removes a callback from this instrument.
toString() String
A string representation of this object.
inherited

Operators

operator ==(Object other) bool
The equality operator.
inherited