FileDocCategorySizeDatePackage
BatteryService.javaAPI DocAndroid 5.1 API37198Thu Mar 12 22:22:42 GMT 2015com.android.server

BatteryService

public final class BatteryService extends SystemService

BatteryService monitors the charging status, and charge level of the device battery. When these values change this service broadcasts the new values to all {@link android.content.BroadcastReceiver IntentReceivers} that are watching the {@link android.content.Intent#ACTION_BATTERY_CHANGED BATTERY_CHANGED} action.

The new values are stored in the Intent data and can be retrieved by calling {@link android.content.Intent#getExtra Intent.getExtra} with the following keys:

"scale" - int, the maximum value for the charge level

"level" - int, charge level, from 0 through "scale" inclusive

"status" - String, the current charging status.

"health" - String, the current battery health.

"present" - boolean, true if the battery is present

"icon-small" - int, suggested small icon to use for this state

"plugged" - int, 0 if the device is not plugged in; 1 if plugged into an AC power adapter; 2 if plugged in via USB.

"voltage" - int, current battery voltage in millivolts

"temperature" - int, current battery temperature in tenths of a degree Centigrade

"technology" - String, the type of battery installed, e.g. "Li-ion"

The battery service may be called by the power manager while holding its locks so we take care to post all outcalls into the activity manager to a handler. FIXME: Ideally the power manager would perform all of its calls into the battery service asynchronously itself.

Fields Summary
private static final String
TAG
private static final boolean
DEBUG
private static final int
BATTERY_SCALE
private int
mCriticalBatteryLevel
private static final int
DUMP_MAX_LENGTH
private static final String[]
DUMPSYS_ARGS
private static final String
DUMPSYS_DATA_PATH
private static final int
BATTERY_PLUGGED_NONE
private final android.content.Context
mContext
private final com.android.internal.app.IBatteryStats
mBatteryStats
private final android.os.Handler
mHandler
private final Object
mLock
private android.os.BatteryProperties
mBatteryProps
private final android.os.BatteryProperties
mLastBatteryProps
private boolean
mBatteryLevelCritical
private int
mLastBatteryStatus
private int
mLastBatteryHealth
private boolean
mLastBatteryPresent
private int
mLastBatteryLevel
private int
mLastBatteryVoltage
private int
mLastBatteryTemperature
private boolean
mLastBatteryLevelCritical
private int
mInvalidCharger
private int
mLastInvalidCharger
private int
mLowBatteryWarningLevel
private int
mLowBatteryCloseWarningLevel
private int
mShutdownBatteryTemperature
private int
mPlugType
private int
mLastPlugType
private boolean
mBatteryLevelLow
private long
mDischargeStartTime
private int
mDischargeStartLevel
private boolean
mUpdatesStopped
private Led
mLed
private boolean
mSentLowBatteryBroadcast
private final android.os.UEventObserver
mInvalidChargerObserver
Constructors Summary
public BatteryService(android.content.Context context)


       
        super(context);

        mContext = context;
        mHandler = new Handler(true /*async*/);
        mLed = new Led(context, getLocalService(LightsManager.class));
        mBatteryStats = BatteryStatsService.getService();

        mCriticalBatteryLevel = mContext.getResources().getInteger(
                com.android.internal.R.integer.config_criticalBatteryWarningLevel);
        mLowBatteryWarningLevel = mContext.getResources().getInteger(
                com.android.internal.R.integer.config_lowBatteryWarningLevel);
        mLowBatteryCloseWarningLevel = mLowBatteryWarningLevel + mContext.getResources().getInteger(
                com.android.internal.R.integer.config_lowBatteryCloseWarningBump);
        mShutdownBatteryTemperature = mContext.getResources().getInteger(
                com.android.internal.R.integer.config_shutdownBatteryTemperature);

        // watch for invalid charger messages if the invalid_charger switch exists
        if (new File("/sys/devices/virtual/switch/invalid_charger/state").exists()) {
            mInvalidChargerObserver.startObserving(
                    "DEVPATH=/devices/virtual/switch/invalid_charger");
        }
Methods Summary
private voiddumpInternal(java.io.PrintWriter pw, java.lang.String[] args)

        synchronized (mLock) {
            if (args == null || args.length == 0 || "-a".equals(args[0])) {
                pw.println("Current Battery Service state:");
                if (mUpdatesStopped) {
                    pw.println("  (UPDATES STOPPED -- use 'reset' to restart)");
                }
                pw.println("  AC powered: " + mBatteryProps.chargerAcOnline);
                pw.println("  USB powered: " + mBatteryProps.chargerUsbOnline);
                pw.println("  Wireless powered: " + mBatteryProps.chargerWirelessOnline);
                pw.println("  status: " + mBatteryProps.batteryStatus);
                pw.println("  health: " + mBatteryProps.batteryHealth);
                pw.println("  present: " + mBatteryProps.batteryPresent);
                pw.println("  level: " + mBatteryProps.batteryLevel);
                pw.println("  scale: " + BATTERY_SCALE);
                pw.println("  voltage: " + mBatteryProps.batteryVoltage);
                pw.println("  temperature: " + mBatteryProps.batteryTemperature);
                pw.println("  technology: " + mBatteryProps.batteryTechnology);
            } else if (args.length == 3 && "set".equals(args[0])) {
                String key = args[1];
                String value = args[2];
                try {
                    if (!mUpdatesStopped) {
                        mLastBatteryProps.set(mBatteryProps);
                    }
                    boolean update = true;
                    if ("ac".equals(key)) {
                        mBatteryProps.chargerAcOnline = Integer.parseInt(value) != 0;
                    } else if ("usb".equals(key)) {
                        mBatteryProps.chargerUsbOnline = Integer.parseInt(value) != 0;
                    } else if ("wireless".equals(key)) {
                        mBatteryProps.chargerWirelessOnline = Integer.parseInt(value) != 0;
                    } else if ("status".equals(key)) {
                        mBatteryProps.batteryStatus = Integer.parseInt(value);
                    } else if ("level".equals(key)) {
                        mBatteryProps.batteryLevel = Integer.parseInt(value);
                    } else if ("invalid".equals(key)) {
                        mInvalidCharger = Integer.parseInt(value);
                    } else {
                        pw.println("Unknown set option: " + key);
                        update = false;
                    }
                    if (update) {
                        long ident = Binder.clearCallingIdentity();
                        try {
                            mUpdatesStopped = true;
                            processValuesLocked(false);
                        } finally {
                            Binder.restoreCallingIdentity(ident);
                        }
                    }
                } catch (NumberFormatException ex) {
                    pw.println("Bad value: " + value);
                }
            } else if (args.length == 1 && "reset".equals(args[0])) {
                long ident = Binder.clearCallingIdentity();
                try {
                    if (mUpdatesStopped) {
                        mUpdatesStopped = false;
                        mBatteryProps.set(mLastBatteryProps);
                        processValuesLocked(false);
                    }
                } finally {
                    Binder.restoreCallingIdentity(ident);
                }
            } else {
                pw.println("Dump current battery state, or:");
                pw.println("  set [ac|usb|wireless|status|level|invalid] <value>");
                pw.println("  reset");
            }
        }
private intgetIconLocked(int level)

        if (mBatteryProps.batteryStatus == BatteryManager.BATTERY_STATUS_CHARGING) {
            return com.android.internal.R.drawable.stat_sys_battery_charge;
        } else if (mBatteryProps.batteryStatus == BatteryManager.BATTERY_STATUS_DISCHARGING) {
            return com.android.internal.R.drawable.stat_sys_battery;
        } else if (mBatteryProps.batteryStatus == BatteryManager.BATTERY_STATUS_NOT_CHARGING
                || mBatteryProps.batteryStatus == BatteryManager.BATTERY_STATUS_FULL) {
            if (isPoweredLocked(BatteryManager.BATTERY_PLUGGED_ANY)
                    && mBatteryProps.batteryLevel >= 100) {
                return com.android.internal.R.drawable.stat_sys_battery_charge;
            } else {
                return com.android.internal.R.drawable.stat_sys_battery;
            }
        } else {
            return com.android.internal.R.drawable.stat_sys_battery_unknown;
        }
private booleanisPoweredLocked(int plugTypeSet)

        // assume we are powered if battery state is unknown so
        // the "stay on while plugged in" option will work.
        if (mBatteryProps.batteryStatus == BatteryManager.BATTERY_STATUS_UNKNOWN) {
            return true;
        }
        if ((plugTypeSet & BatteryManager.BATTERY_PLUGGED_AC) != 0 && mBatteryProps.chargerAcOnline) {
            return true;
        }
        if ((plugTypeSet & BatteryManager.BATTERY_PLUGGED_USB) != 0 && mBatteryProps.chargerUsbOnline) {
            return true;
        }
        if ((plugTypeSet & BatteryManager.BATTERY_PLUGGED_WIRELESS) != 0 && mBatteryProps.chargerWirelessOnline) {
            return true;
        }
        return false;
private voidlogBatteryStatsLocked()

        IBinder batteryInfoService = ServiceManager.getService(BatteryStats.SERVICE_NAME);
        if (batteryInfoService == null) return;

        DropBoxManager db = (DropBoxManager) mContext.getSystemService(Context.DROPBOX_SERVICE);
        if (db == null || !db.isTagEnabled("BATTERY_DISCHARGE_INFO")) return;

        File dumpFile = null;
        FileOutputStream dumpStream = null;
        try {
            // dump the service to a file
            dumpFile = new File(DUMPSYS_DATA_PATH + BatteryStats.SERVICE_NAME + ".dump");
            dumpStream = new FileOutputStream(dumpFile);
            batteryInfoService.dump(dumpStream.getFD(), DUMPSYS_ARGS);
            FileUtils.sync(dumpStream);

            // add dump file to drop box
            db.addFile("BATTERY_DISCHARGE_INFO", dumpFile, DropBoxManager.IS_TEXT);
        } catch (RemoteException e) {
            Slog.e(TAG, "failed to dump battery service", e);
        } catch (IOException e) {
            Slog.e(TAG, "failed to write dumpsys file", e);
        } finally {
            // make sure we clean up
            if (dumpStream != null) {
                try {
                    dumpStream.close();
                } catch (IOException e) {
                    Slog.e(TAG, "failed to close dumpsys output stream");
                }
            }
            if (dumpFile != null && !dumpFile.delete()) {
                Slog.e(TAG, "failed to delete temporary dumpsys file: "
                        + dumpFile.getAbsolutePath());
            }
        }
private voidlogOutlierLocked(long duration)

        ContentResolver cr = mContext.getContentResolver();
        String dischargeThresholdString = Settings.Global.getString(cr,
                Settings.Global.BATTERY_DISCHARGE_THRESHOLD);
        String durationThresholdString = Settings.Global.getString(cr,
                Settings.Global.BATTERY_DISCHARGE_DURATION_THRESHOLD);

        if (dischargeThresholdString != null && durationThresholdString != null) {
            try {
                long durationThreshold = Long.parseLong(durationThresholdString);
                int dischargeThreshold = Integer.parseInt(dischargeThresholdString);
                if (duration <= durationThreshold &&
                        mDischargeStartLevel - mBatteryProps.batteryLevel >= dischargeThreshold) {
                    // If the discharge cycle is bad enough we want to know about it.
                    logBatteryStatsLocked();
                }
                if (DEBUG) Slog.v(TAG, "duration threshold: " + durationThreshold +
                        " discharge threshold: " + dischargeThreshold);
                if (DEBUG) Slog.v(TAG, "duration: " + duration + " discharge: " +
                        (mDischargeStartLevel - mBatteryProps.batteryLevel));
            } catch (NumberFormatException e) {
                Slog.e(TAG, "Invalid DischargeThresholds GService string: " +
                        durationThresholdString + " or " + dischargeThresholdString);
                return;
            }
        }
public voidonBootPhase(int phase)

        if (phase == PHASE_ACTIVITY_MANAGER_READY) {
            // check our power situation now that it is safe to display the shutdown dialog.
            synchronized (mLock) {
                ContentObserver obs = new ContentObserver(mHandler) {
                    @Override
                    public void onChange(boolean selfChange) {
                        synchronized (mLock) {
                            updateBatteryWarningLevelLocked();
                        }
                    }
                };
                final ContentResolver resolver = mContext.getContentResolver();
                resolver.registerContentObserver(Settings.Global.getUriFor(
                        Settings.Global.LOW_POWER_MODE_TRIGGER_LEVEL),
                        false, obs, UserHandle.USER_ALL);
                updateBatteryWarningLevelLocked();
            }
        }
public voidonStart()

        IBinder b = ServiceManager.getService("batteryproperties");
        final IBatteryPropertiesRegistrar batteryPropertiesRegistrar =
                IBatteryPropertiesRegistrar.Stub.asInterface(b);
        try {
            batteryPropertiesRegistrar.registerListener(new BatteryListener());
        } catch (RemoteException e) {
            // Should never happen.
        }

        publishBinderService("battery", new BinderService());
        publishLocalService(BatteryManagerInternal.class, new LocalService());
private voidprocessValuesLocked(boolean force)

        boolean logOutlier = false;
        long dischargeDuration = 0;

        mBatteryLevelCritical = (mBatteryProps.batteryLevel <= mCriticalBatteryLevel);
        if (mBatteryProps.chargerAcOnline) {
            mPlugType = BatteryManager.BATTERY_PLUGGED_AC;
        } else if (mBatteryProps.chargerUsbOnline) {
            mPlugType = BatteryManager.BATTERY_PLUGGED_USB;
        } else if (mBatteryProps.chargerWirelessOnline) {
            mPlugType = BatteryManager.BATTERY_PLUGGED_WIRELESS;
        } else {
            mPlugType = BATTERY_PLUGGED_NONE;
        }

        if (DEBUG) {
            Slog.d(TAG, "Processing new values: "
                    + "chargerAcOnline=" + mBatteryProps.chargerAcOnline
                    + ", chargerUsbOnline=" + mBatteryProps.chargerUsbOnline
                    + ", chargerWirelessOnline=" + mBatteryProps.chargerWirelessOnline
                    + ", batteryStatus=" + mBatteryProps.batteryStatus
                    + ", batteryHealth=" + mBatteryProps.batteryHealth
                    + ", batteryPresent=" + mBatteryProps.batteryPresent
                    + ", batteryLevel=" + mBatteryProps.batteryLevel
                    + ", batteryTechnology=" + mBatteryProps.batteryTechnology
                    + ", batteryVoltage=" + mBatteryProps.batteryVoltage
                    + ", batteryTemperature=" + mBatteryProps.batteryTemperature
                    + ", mBatteryLevelCritical=" + mBatteryLevelCritical
                    + ", mPlugType=" + mPlugType);
        }

        // Let the battery stats keep track of the current level.
        try {
            mBatteryStats.setBatteryState(mBatteryProps.batteryStatus, mBatteryProps.batteryHealth,
                    mPlugType, mBatteryProps.batteryLevel, mBatteryProps.batteryTemperature,
                    mBatteryProps.batteryVoltage);
        } catch (RemoteException e) {
            // Should never happen.
        }

        shutdownIfNoPowerLocked();
        shutdownIfOverTempLocked();

        if (force || (mBatteryProps.batteryStatus != mLastBatteryStatus ||
                mBatteryProps.batteryHealth != mLastBatteryHealth ||
                mBatteryProps.batteryPresent != mLastBatteryPresent ||
                mBatteryProps.batteryLevel != mLastBatteryLevel ||
                mPlugType != mLastPlugType ||
                mBatteryProps.batteryVoltage != mLastBatteryVoltage ||
                mBatteryProps.batteryTemperature != mLastBatteryTemperature ||
                mInvalidCharger != mLastInvalidCharger)) {

            if (mPlugType != mLastPlugType) {
                if (mLastPlugType == BATTERY_PLUGGED_NONE) {
                    // discharging -> charging

                    // There's no value in this data unless we've discharged at least once and the
                    // battery level has changed; so don't log until it does.
                    if (mDischargeStartTime != 0 && mDischargeStartLevel != mBatteryProps.batteryLevel) {
                        dischargeDuration = SystemClock.elapsedRealtime() - mDischargeStartTime;
                        logOutlier = true;
                        EventLog.writeEvent(EventLogTags.BATTERY_DISCHARGE, dischargeDuration,
                                mDischargeStartLevel, mBatteryProps.batteryLevel);
                        // make sure we see a discharge event before logging again
                        mDischargeStartTime = 0;
                    }
                } else if (mPlugType == BATTERY_PLUGGED_NONE) {
                    // charging -> discharging or we just powered up
                    mDischargeStartTime = SystemClock.elapsedRealtime();
                    mDischargeStartLevel = mBatteryProps.batteryLevel;
                }
            }
            if (mBatteryProps.batteryStatus != mLastBatteryStatus ||
                    mBatteryProps.batteryHealth != mLastBatteryHealth ||
                    mBatteryProps.batteryPresent != mLastBatteryPresent ||
                    mPlugType != mLastPlugType) {
                EventLog.writeEvent(EventLogTags.BATTERY_STATUS,
                        mBatteryProps.batteryStatus, mBatteryProps.batteryHealth, mBatteryProps.batteryPresent ? 1 : 0,
                        mPlugType, mBatteryProps.batteryTechnology);
            }
            if (mBatteryProps.batteryLevel != mLastBatteryLevel) {
                // Don't do this just from voltage or temperature changes, that is
                // too noisy.
                EventLog.writeEvent(EventLogTags.BATTERY_LEVEL,
                        mBatteryProps.batteryLevel, mBatteryProps.batteryVoltage, mBatteryProps.batteryTemperature);
            }
            if (mBatteryLevelCritical && !mLastBatteryLevelCritical &&
                    mPlugType == BATTERY_PLUGGED_NONE) {
                // We want to make sure we log discharge cycle outliers
                // if the battery is about to die.
                dischargeDuration = SystemClock.elapsedRealtime() - mDischargeStartTime;
                logOutlier = true;
            }

            if (!mBatteryLevelLow) {
                // Should we now switch in to low battery mode?
                if (mPlugType == BATTERY_PLUGGED_NONE
                        && mBatteryProps.batteryLevel <= mLowBatteryWarningLevel) {
                    mBatteryLevelLow = true;
                }
            } else {
                // Should we now switch out of low battery mode?
                if (mPlugType != BATTERY_PLUGGED_NONE) {
                    mBatteryLevelLow = false;
                } else if (mBatteryProps.batteryLevel >= mLowBatteryCloseWarningLevel)  {
                    mBatteryLevelLow = false;
                } else if (force && mBatteryProps.batteryLevel >= mLowBatteryWarningLevel) {
                    // If being forced, the previous state doesn't matter, we will just
                    // absolutely check to see if we are now above the warning level.
                    mBatteryLevelLow = false;
                }
            }

            sendIntentLocked();

            // Separate broadcast is sent for power connected / not connected
            // since the standard intent will not wake any applications and some
            // applications may want to have smart behavior based on this.
            if (mPlugType != 0 && mLastPlugType == 0) {
                mHandler.post(new Runnable() {
                    @Override
                    public void run() {
                        Intent statusIntent = new Intent(Intent.ACTION_POWER_CONNECTED);
                        statusIntent.setFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY_BEFORE_BOOT);
                        mContext.sendBroadcastAsUser(statusIntent, UserHandle.ALL);
                    }
                });
            }
            else if (mPlugType == 0 && mLastPlugType != 0) {
                mHandler.post(new Runnable() {
                    @Override
                    public void run() {
                        Intent statusIntent = new Intent(Intent.ACTION_POWER_DISCONNECTED);
                        statusIntent.setFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY_BEFORE_BOOT);
                        mContext.sendBroadcastAsUser(statusIntent, UserHandle.ALL);
                    }
                });
            }

            if (shouldSendBatteryLowLocked()) {
                mSentLowBatteryBroadcast = true;
                mHandler.post(new Runnable() {
                    @Override
                    public void run() {
                        Intent statusIntent = new Intent(Intent.ACTION_BATTERY_LOW);
                        statusIntent.setFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY_BEFORE_BOOT);
                        mContext.sendBroadcastAsUser(statusIntent, UserHandle.ALL);
                    }
                });
            } else if (mSentLowBatteryBroadcast && mLastBatteryLevel >= mLowBatteryCloseWarningLevel) {
                mSentLowBatteryBroadcast = false;
                mHandler.post(new Runnable() {
                    @Override
                    public void run() {
                        Intent statusIntent = new Intent(Intent.ACTION_BATTERY_OKAY);
                        statusIntent.setFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY_BEFORE_BOOT);
                        mContext.sendBroadcastAsUser(statusIntent, UserHandle.ALL);
                    }
                });
            }

            // Update the battery LED
            mLed.updateLightsLocked();

            // This needs to be done after sendIntent() so that we get the lastest battery stats.
            if (logOutlier && dischargeDuration != 0) {
                logOutlierLocked(dischargeDuration);
            }

            mLastBatteryStatus = mBatteryProps.batteryStatus;
            mLastBatteryHealth = mBatteryProps.batteryHealth;
            mLastBatteryPresent = mBatteryProps.batteryPresent;
            mLastBatteryLevel = mBatteryProps.batteryLevel;
            mLastPlugType = mPlugType;
            mLastBatteryVoltage = mBatteryProps.batteryVoltage;
            mLastBatteryTemperature = mBatteryProps.batteryTemperature;
            mLastBatteryLevelCritical = mBatteryLevelCritical;
            mLastInvalidCharger = mInvalidCharger;
        }
private voidsendIntentLocked()

        //  Pack up the values and broadcast them to everyone
        final Intent intent = new Intent(Intent.ACTION_BATTERY_CHANGED);
        intent.addFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY
                | Intent.FLAG_RECEIVER_REPLACE_PENDING);

        int icon = getIconLocked(mBatteryProps.batteryLevel);

        intent.putExtra(BatteryManager.EXTRA_STATUS, mBatteryProps.batteryStatus);
        intent.putExtra(BatteryManager.EXTRA_HEALTH, mBatteryProps.batteryHealth);
        intent.putExtra(BatteryManager.EXTRA_PRESENT, mBatteryProps.batteryPresent);
        intent.putExtra(BatteryManager.EXTRA_LEVEL, mBatteryProps.batteryLevel);
        intent.putExtra(BatteryManager.EXTRA_SCALE, BATTERY_SCALE);
        intent.putExtra(BatteryManager.EXTRA_ICON_SMALL, icon);
        intent.putExtra(BatteryManager.EXTRA_PLUGGED, mPlugType);
        intent.putExtra(BatteryManager.EXTRA_VOLTAGE, mBatteryProps.batteryVoltage);
        intent.putExtra(BatteryManager.EXTRA_TEMPERATURE, mBatteryProps.batteryTemperature);
        intent.putExtra(BatteryManager.EXTRA_TECHNOLOGY, mBatteryProps.batteryTechnology);
        intent.putExtra(BatteryManager.EXTRA_INVALID_CHARGER, mInvalidCharger);

        if (DEBUG) {
            Slog.d(TAG, "Sending ACTION_BATTERY_CHANGED.  level:" + mBatteryProps.batteryLevel +
                    ", scale:" + BATTERY_SCALE + ", status:" + mBatteryProps.batteryStatus +
                    ", health:" + mBatteryProps.batteryHealth +  ", present:" + mBatteryProps.batteryPresent +
                    ", voltage: " + mBatteryProps.batteryVoltage +
                    ", temperature: " + mBatteryProps.batteryTemperature +
                    ", technology: " + mBatteryProps.batteryTechnology +
                    ", AC powered:" + mBatteryProps.chargerAcOnline + ", USB powered:" + mBatteryProps.chargerUsbOnline +
                    ", Wireless powered:" + mBatteryProps.chargerWirelessOnline +
                    ", icon:" + icon  + ", invalid charger:" + mInvalidCharger);
        }

        mHandler.post(new Runnable() {
            @Override
            public void run() {
                ActivityManagerNative.broadcastStickyIntent(intent, null, UserHandle.USER_ALL);
            }
        });
private booleanshouldSendBatteryLowLocked()

        final boolean plugged = mPlugType != BATTERY_PLUGGED_NONE;
        final boolean oldPlugged = mLastPlugType != BATTERY_PLUGGED_NONE;

        /* The ACTION_BATTERY_LOW broadcast is sent in these situations:
         * - is just un-plugged (previously was plugged) and battery level is
         *   less than or equal to WARNING, or
         * - is not plugged and battery level falls to WARNING boundary
         *   (becomes <= mLowBatteryWarningLevel).
         */
        return !plugged
                && mBatteryProps.batteryStatus != BatteryManager.BATTERY_STATUS_UNKNOWN
                && mBatteryProps.batteryLevel <= mLowBatteryWarningLevel
                && (oldPlugged || mLastBatteryLevel > mLowBatteryWarningLevel);
private voidshutdownIfNoPowerLocked()

        // shut down gracefully if our battery is critically low and we are not powered.
        // wait until the system has booted before attempting to display the shutdown dialog.
        if (mBatteryProps.batteryLevel == 0 && !isPoweredLocked(BatteryManager.BATTERY_PLUGGED_ANY)) {
            mHandler.post(new Runnable() {
                @Override
                public void run() {
                    if (ActivityManagerNative.isSystemReady()) {
                        Intent intent = new Intent(Intent.ACTION_REQUEST_SHUTDOWN);
                        intent.putExtra(Intent.EXTRA_KEY_CONFIRM, false);
                        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                        mContext.startActivityAsUser(intent, UserHandle.CURRENT);
                    }
                }
            });
        }
private voidshutdownIfOverTempLocked()

        // shut down gracefully if temperature is too high (> 68.0C by default)
        // wait until the system has booted before attempting to display the
        // shutdown dialog.
        if (mBatteryProps.batteryTemperature > mShutdownBatteryTemperature) {
            mHandler.post(new Runnable() {
                @Override
                public void run() {
                    if (ActivityManagerNative.isSystemReady()) {
                        Intent intent = new Intent(Intent.ACTION_REQUEST_SHUTDOWN);
                        intent.putExtra(Intent.EXTRA_KEY_CONFIRM, false);
                        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                        mContext.startActivityAsUser(intent, UserHandle.CURRENT);
                    }
                }
            });
        }
private voidupdate(android.os.BatteryProperties props)

        synchronized (mLock) {
            if (!mUpdatesStopped) {
                mBatteryProps = props;
                // Process the new values.
                processValuesLocked(false);
            } else {
                mLastBatteryProps.set(props);
            }
        }
private voidupdateBatteryWarningLevelLocked()

        final ContentResolver resolver = mContext.getContentResolver();
        int defWarnLevel = mContext.getResources().getInteger(
                com.android.internal.R.integer.config_lowBatteryWarningLevel);
        mLowBatteryWarningLevel = Settings.Global.getInt(resolver,
                Settings.Global.LOW_POWER_MODE_TRIGGER_LEVEL, defWarnLevel);
        if (mLowBatteryWarningLevel == 0) {
            mLowBatteryWarningLevel = defWarnLevel;
        }
        if (mLowBatteryWarningLevel < mCriticalBatteryLevel) {
            mLowBatteryWarningLevel = mCriticalBatteryLevel;
        }
        mLowBatteryCloseWarningLevel = mLowBatteryWarningLevel + mContext.getResources().getInteger(
                com.android.internal.R.integer.config_lowBatteryCloseWarningBump);
        processValuesLocked(true);