Probe class Null safety

A Probe is responsible for collecting data.

A probe's state can be set using the initialize, resume, pause, and stop methods. A restart can be used to restart a probe when its measure has changed (e.g. disabling the probe). A probe can be stopped at any time. If an error occurs the state of a probe becomes undefined. This is, for example, used when an exception is caught or when a probe is not available (e.g. on iOS).

The state property reveals the probe's current runtime state. The stateEvents is a stream of state changes which can be listen to as a broadcast stream.

Probes return sensed data in a Stream as data. This is the main usage of a probe. For example, to listens to events and print them;

probe.data.forEach(print);
Implementers

Constructors

Probe()

Properties

data Stream<DataPoint>
The stream of DataPoint generated from this probe.
read-only
enabled bool
Is this probe enabled, i.e. available for collection of data using the resume method.
read-only
hashCode int
The hash code for this object. [...]
read-only, inherited
measure Measure?
The Measure that configures this probe.
read-only
name String
A printer-friendly name for this probe.
read-only
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
state ProbeState
The runtime state of this probe.
read-only
stateEvents Stream<ProbeState>
The runtime state changes of this probe. [...]
read-only
type String
The type of this probe according to String.
read-only

Methods

initialize(Measure measure) → void
Initialize the probe before starting it. [...]
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
inherited
pause() → void
Pause the probe. The probe is paused until resume or restart is called.
restart() → void
Restart the probe. [...]
resume() → void
Resume the probe.
stop() → void
Stop the probe. Once a probe is stopped, it cannot be started again. If you need to restart a probe, use the restart or pause and resume methods.
toString() String
A string representation of this object. [...]
inherited
validNextState(ProbeState nextState) bool
Is ProbeState a valid next state for this probe? [...]

Operators

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