com.facebook.battery.metrics.camera

Class CameraMetricsCollector

java.lang.Object

com.facebook.battery.metrics.api.SystemMetricsCollector<CameraMetrics>

com.facebook.battery.metrics.camera.CameraMetricsCollector

@ThreadSafe
public class CameraMetricsCollector
extends SystemMetricsCollector<CameraMetrics>

CameraMetricsCollector internally maintains how long the camera was open and previewed; this is simply a helper class to maintain state and can't automatically instrument camera usage.

The collector exposes camera open/close, preview open/close and error recording functions that can be passed a Camera or a CameraDevice object and will track times accordingly.

- For Camera1, - Camera#open(), Camera#open(int) -> recordCameraOpen(Object) - Camera#release() -> recordCameraClose(Object) - Camera#startPreview() -> recordPreviewStart(Object) - Camera#stopPreview() -> recordPreviewStop(Object) - Camera.ErrorCallback#onError(int, Camera) -> recordCameraError(Object) - For Camera2, - CameraDevice.StateCallback#onOpened(CameraDevice) -> recordCameraOpen(Object) - CameraDevice.StateCallback#onClosed(CameraDevice) -> recordCameraClose(Object) - CameraDevice.StateCallback#onError(CameraDevice, int) -> recordCameraError(Object) - CameraCaptureSession#setRepeatingRequest(CaptureRequest, CameraCaptureSession.CaptureCallback, Handler) -> recordPreviewStart(Object) - CameraCaptureSession#close() -> recordPreviewStop(Object) - CameraDevice#close -> recordCameraClose(Object)

Constructor Summary

Constructors

Constructor and Description
CameraMetricsCollector()

Method Summary

Modifier and Type	Method and Description
CameraMetrics	createMetrics() Creates an empty instance of the corresponding system metrics.
boolean	getSnapshot(CameraMetrics snapshot) Note that access to snapshot instances is not synchronized and must be taken care of by the caller requesting getSnapshot.
void	recordCameraClose(java.lang.Object camera)
void	recordCameraError(java.lang.Object camera)
void	recordCameraOpen(java.lang.Object camera)
void	recordPreviewStart(java.lang.Object camera)
void	recordPreviewStop(java.lang.Object camera)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CameraMetricsCollector

public CameraMetricsCollector()

Method Detail

getSnapshot

public boolean getSnapshot(CameraMetrics snapshot)

Description copied from class: SystemMetricsCollector

Note that access to snapshot instances is not synchronized and must be taken care of by the caller requesting getSnapshot.

Specified by:

getSnapshot in class SystemMetricsCollector<CameraMetrics>

Parameters:

snapshot - snapshot on which the data will be written

Returns:

true if the snapshot has been updated with valid data.

createMetrics

public CameraMetrics createMetrics()

Description copied from class: SystemMetricsCollector

Creates an empty instance of the corresponding system metrics.

Explicitly having this function available reduces a significant amount of boilerplate

Specified by:

createMetrics in class SystemMetricsCollector<CameraMetrics>

Returns:

New System Metrics object

recordCameraOpen

public void recordCameraOpen(java.lang.Object camera)

recordCameraClose

public void recordCameraClose(java.lang.Object camera)

recordPreviewStart

public void recordPreviewStart(java.lang.Object camera)

recordPreviewStop

public void recordPreviewStop(java.lang.Object camera)

recordCameraError

public void recordCameraError(java.lang.Object camera)