# Package org.apache.jmeter.visualizers.backend

Interface Summary
Backend: Identifies Backend components
BackendListenerClient: This interface defines the interactions between the `BackendListener` and external Java programs which can be executed by JMeter.

Class Summary
AbstractBackendListenerClient: An abstract implementation of the BackendListenerClient interface.
BackendListener: Async Listener that delegates SampleResult handling to implementations of `BackendListenerClient`
BackendListenerContext: BackendListenerContext is used to provide context information to a BackendListenerClient implementation.
BackendListenerGui: The `BackendListenerGui` class provides the user interface for the `BackendListener` object.
ErrorMetric: Object representing an error by a response code and response message
SamplerMetric: Sampler metric
UserMetric: User metric

Enum Summary
WindowMode: Metrics are sent into boxes which can be `a fixed-size sliding window` or `time boxed`.