com.reelyactive.blesdk.support.ble

Class BluetoothCrashResolver

java.lang.Object

com.reelyactive.blesdk.support.ble.BluetoothCrashResolver

public class BluetoothCrashResolver
extends java.lang.Object

This class provides relief for Android Bug 67272. This bug in the Bluedroid stack causes crashes in Android's BluetoothService when scanning for BLE devices encounters a large number of unique devices. It is rare for most users but can be problematic for those with apps scanning for Bluetooth LE devices in the background (e.g. iBeacon-enabled apps), especially when these users are around Bluetooth LE devices that randomize their mac address like Gimbal beacons.

This class can both recover from crashes and prevent crashes from happening in the first place

More details on the bug can be found at the following URLs:

https://code.google.com/p/android/issues/detail?id=67272 https://github.com/RadiusNetworks/android-ibeacon-service/issues/16

Version 1.0

Created by dyoung on 3/24/14.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	BluetoothCrashResolver.UpdateNotifier

Constructor Summary

Constructors

Constructor and Description
BluetoothCrashResolver(android.content.Context context) Constructor should be called only once per long-running process that does Bluetooth LE scanning.

Method Summary

Methods

Modifier and Type	Method and Description
void	crashDetected()
void	disableDebug() Disable debug logging
void	enableDebug() Enable debug logging.
void	forceFlush() Used to force a recovery operation
int	getDetectedCrashCount()
long	getLastBluetoothCrashDetectionTime()
int	getRecoveryAttemptCount()
boolean	isLastRecoverySucceeded()
boolean	isRecoveryInProgress()
void	notifyScannedDevice(android.bluetooth.BluetoothDevice device, android.bluetooth.BluetoothAdapter.LeScanCallback scanner) Call this method from your BluetoothAdapter.LeScanCallback method.
void	setUpdateNotifier(BluetoothCrashResolver.UpdateNotifier updateNotifier)
void	start() Starts looking for crashes of the Bluetooth LE system and taking proactive steps to stop crashes from happening.
void	stop() Stops looking for crashes.

Methods inherited from class java.lang.Object

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

Constructor Detail

BluetoothCrashResolver

public BluetoothCrashResolver(android.content.Context context)

Constructor should be called only once per long-running process that does Bluetooth LE scanning. Must call start() to make it do anything.

Parameters:

context - the Activity or Service that is doing the Bluetooth scanning

Method Detail

start

public void start()

Starts looking for crashes of the Bluetooth LE system and taking proactive steps to stop crashes from happening. Proactive steps require calls to notifyScannedDevice(Device device) so that crashes can be predicted ahead of time.

stop

public void stop()

Stops looking for crashes. Does not need to be called in normal operations, but may be useful for testing.

enableDebug

public void enableDebug()

Enable debug logging. By default no debug lines are logged.

disableDebug

public void disableDebug()

Disable debug logging

notifyScannedDevice

public void notifyScannedDevice(android.bluetooth.BluetoothDevice device,
                       android.bluetooth.BluetoothAdapter.LeScanCallback scanner)

Call this method from your BluetoothAdapter.LeScanCallback method. Doing so is optional, but if you do, this class will be able to count the number of disctinct bluetooth devices scanned, and prevent crashes before they happen.

This works very well if the app containing this class is the only one running bluetooth LE scans on the device, or it is constantly doing scans (e.g. is in the foreground for extended periods of time.)

This will not work well if the application using this class is only scanning periodically (e.g. when in the background to save battery) and another application is also scanning on the same device, because this class will only get the counts from this application.

Future augmentation of this class may improve this by somehow centralizing the list of unique scanned devices.

Parameters:

device -

crashDetected

public void crashDetected()

getLastBluetoothCrashDetectionTime

public long getLastBluetoothCrashDetectionTime()

getDetectedCrashCount

public int getDetectedCrashCount()

getRecoveryAttemptCount

public int getRecoveryAttemptCount()

isLastRecoverySucceeded

public boolean isLastRecoverySucceeded()

isRecoveryInProgress

public boolean isRecoveryInProgress()

setUpdateNotifier

public void setUpdateNotifier(BluetoothCrashResolver.UpdateNotifier updateNotifier)

forceFlush

public void forceFlush()

Used to force a recovery operation