1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17
18package android.hardware;
19
20import android.os.Build;
21import android.annotation.SystemApi;
22
23/**
24 * Class representing a sensor. Use {@link SensorManager#getSensorList} to get
25 * the list of available Sensors.
26 *
27 * @see SensorManager
28 * @see SensorEventListener
29 * @see SensorEvent
30 *
31 */
32public final class Sensor {
33
34    /**
35     * A constant describing an accelerometer sensor type.
36     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
37     * for more details.
38     */
39    public static final int TYPE_ACCELEROMETER = 1;
40
41    /**
42     * A constant string describing an accelerometer sensor type.
43     *
44     * @see #TYPE_ACCELEROMETER
45     */
46    public static final String STRING_TYPE_ACCELEROMETER = "android.sensor.accelerometer";
47
48    /**
49     * A constant describing a magnetic field sensor type.
50     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
51     * for more details.
52     */
53    public static final int TYPE_MAGNETIC_FIELD = 2;
54
55    /**
56     * A constant string describing a magnetic field sensor type.
57     *
58     * @see #TYPE_MAGNETIC_FIELD
59     */
60    public static final String STRING_TYPE_MAGNETIC_FIELD = "android.sensor.magnetic_field";
61
62    /**
63     * A constant describing an orientation sensor type.
64     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
65     * for more details.
66     *
67     * @deprecated use {@link android.hardware.SensorManager#getOrientation
68     *             SensorManager.getOrientation()} instead.
69     */
70    @Deprecated
71    public static final int TYPE_ORIENTATION = 3;
72
73    /**
74     * A constant string describing an orientation sensor type.
75     *
76     * @see #TYPE_ORIENTATION
77     * @deprecated use {@link android.hardware.SensorManager#getOrientation
78     *             SensorManager.getOrientation()} instead.
79     */
80    @Deprecated
81    public static final String STRING_TYPE_ORIENTATION = "android.sensor.orientation";
82
83    /**
84     * A constant describing a gyroscope sensor type.
85     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
86     * for more details. */
87    public static final int TYPE_GYROSCOPE = 4;
88
89    /**
90     * A constant string describing a gyroscope sensor type.
91     *
92     * @see #TYPE_GYROSCOPE
93     */
94    public static final String STRING_TYPE_GYROSCOPE = "android.sensor.gyroscope";
95
96    /**
97     * A constant describing a light sensor type.
98     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
99     * for more details.
100     */
101    public static final int TYPE_LIGHT = 5;
102
103    /**
104     * A constant string describing a light sensor type.
105     *
106     * @see #TYPE_LIGHT
107     */
108    public static final String STRING_TYPE_LIGHT = "android.sensor.light";
109
110    /**
111     * A constant describing a pressure sensor type.
112     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
113     * for more details.
114     */
115    public static final int TYPE_PRESSURE = 6;
116
117    /**
118     * A constant string describing a pressure sensor type.
119     *
120     * @see #TYPE_PRESSURE
121     */
122    public static final String STRING_TYPE_PRESSURE = "android.sensor.pressure";
123
124    /**
125     * A constant describing a temperature sensor type
126     *
127     * @deprecated use
128     *             {@link android.hardware.Sensor#TYPE_AMBIENT_TEMPERATURE
129     *             Sensor.TYPE_AMBIENT_TEMPERATURE} instead.
130     */
131    @Deprecated
132    public static final int TYPE_TEMPERATURE = 7;
133
134    /**
135     * A constant string describing a temperature sensor type
136     *
137     * @see #TYPE_TEMPERATURE
138     * @deprecated use
139     *             {@link android.hardware.Sensor#STRING_TYPE_AMBIENT_TEMPERATURE
140     *             Sensor.STRING_TYPE_AMBIENT_TEMPERATURE} instead.
141     */
142    @Deprecated
143    public static final String STRING_TYPE_TEMPERATURE = "android.sensor.temperature";
144
145    /**
146     * A constant describing a proximity sensor type. This is a wake up sensor.
147     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
148     * for more details.
149     * @see #isWakeUpSensor()
150     */
151    public static final int TYPE_PROXIMITY = 8;
152
153    /**
154     * A constant string describing a proximity sensor type.
155     *
156     * @see #TYPE_PROXIMITY
157     */
158    public static final String STRING_TYPE_PROXIMITY = "android.sensor.proximity";
159
160    /**
161     * A constant describing a gravity sensor type.
162     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
163     * for more details.
164     */
165    public static final int TYPE_GRAVITY = 9;
166
167    /**
168     * A constant string describing a gravity sensor type.
169     *
170     * @see #TYPE_GRAVITY
171     */
172    public static final String STRING_TYPE_GRAVITY = "android.sensor.gravity";
173
174    /**
175     * A constant describing a linear acceleration sensor type.
176     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
177     * for more details.
178     */
179    public static final int TYPE_LINEAR_ACCELERATION = 10;
180
181    /**
182     * A constant string describing a linear acceleration sensor type.
183     *
184     * @see #TYPE_LINEAR_ACCELERATION
185     */
186    public static final String STRING_TYPE_LINEAR_ACCELERATION =
187        "android.sensor.linear_acceleration";
188
189    /**
190     * A constant describing a rotation vector sensor type.
191     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
192     * for more details.
193     */
194    public static final int TYPE_ROTATION_VECTOR = 11;
195
196    /**
197     * A constant string describing a rotation vector sensor type.
198     *
199     * @see #TYPE_ROTATION_VECTOR
200     */
201    public static final String STRING_TYPE_ROTATION_VECTOR = "android.sensor.rotation_vector";
202
203    /**
204     * A constant describing a relative humidity sensor type.
205     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
206     * for more details.
207     */
208    public static final int TYPE_RELATIVE_HUMIDITY = 12;
209
210    /**
211     * A constant string describing a relative humidity sensor type
212     *
213     * @see #TYPE_RELATIVE_HUMIDITY
214     */
215    public static final String STRING_TYPE_RELATIVE_HUMIDITY = "android.sensor.relative_humidity";
216
217    /**
218     * A constant describing an ambient temperature sensor type.
219     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values}
220     * for more details.
221     */
222    public static final int TYPE_AMBIENT_TEMPERATURE = 13;
223
224    /**
225     * A constant string describing an ambient temperature sensor type.
226     *
227     * @see #TYPE_AMBIENT_TEMPERATURE
228     */
229    public static final String STRING_TYPE_AMBIENT_TEMPERATURE =
230        "android.sensor.ambient_temperature";
231
232    /**
233     * A constant describing an uncalibrated magnetic field sensor type.
234     * <p>
235     * Similar to {@link #TYPE_MAGNETIC_FIELD} but the hard iron calibration (device calibration
236     * due to distortions that arise from magnetized iron, steel or permanent magnets on the
237     * device) is not considered in the given sensor values. However, such hard iron bias values
238     * are returned to you separately in the result {@link android.hardware.SensorEvent#values}
239     * so you may use them for custom calibrations.
240     * <p>Also, no periodic calibration is performed
241     * (i.e. there are no discontinuities in the data stream while using this sensor) and
242     * assumptions that the magnetic field is due to the Earth's poles is avoided, but
243     * factory calibration and temperature compensation have been performed.
244     * </p>
245     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values} for more
246     * details.
247     */
248    public static final int TYPE_MAGNETIC_FIELD_UNCALIBRATED = 14;
249    /**
250     * A constant string describing an uncalibrated magnetic field sensor type.
251     *
252     * @see #TYPE_MAGNETIC_FIELD_UNCALIBRATED
253     */
254    public static final String STRING_TYPE_MAGNETIC_FIELD_UNCALIBRATED =
255        "android.sensor.magnetic_field_uncalibrated";
256
257    /**
258     * A constant describing an uncalibrated rotation vector sensor type.
259     * <p>Identical to {@link #TYPE_ROTATION_VECTOR} except that it doesn't
260     * use the geomagnetic field. Therefore the Y axis doesn't
261     * point north, but instead to some other reference, that reference is
262     * allowed to drift by the same order of magnitude as the gyroscope
263     * drift around the Z axis.
264     * <p>
265     * In the ideal case, a phone rotated and returning to the same real-world
266     * orientation should report the same game rotation vector
267     * (without using the earth's geomagnetic field). However, the orientation
268     * may drift somewhat over time.
269     * </p>
270     * <p>See {@link android.hardware.SensorEvent#values SensorEvent.values} for more
271     * details.
272     */
273    public static final int TYPE_GAME_ROTATION_VECTOR = 15;
274
275    /**
276     * A constant string describing an uncalibrated rotation vector sensor type.
277     *
278     * @see #TYPE_GAME_ROTATION_VECTOR
279     */
280    public static final String STRING_TYPE_GAME_ROTATION_VECTOR =
281        "android.sensor.game_rotation_vector";
282
283    /**
284     * A constant describing an uncalibrated gyroscope sensor type.
285     * <p>Similar to {@link #TYPE_GYROSCOPE} but no gyro-drift compensation has been performed
286     * to adjust the given sensor values. However, such gyro-drift bias values
287     * are returned to you separately in the result {@link android.hardware.SensorEvent#values}
288     * so you may use them for custom calibrations.
289     * <p>Factory calibration and temperature compensation is still applied
290     * to the rate of rotation (angular speeds).
291     * </p>
292     * <p> See {@link android.hardware.SensorEvent#values SensorEvent.values} for more
293     * details.
294     */
295    public static final int TYPE_GYROSCOPE_UNCALIBRATED = 16;
296
297    /**
298     * A constant string describing an uncalibrated gyroscope sensor type.
299     *
300     * @see #TYPE_GYROSCOPE_UNCALIBRATED
301     */
302    public static final String STRING_TYPE_GYROSCOPE_UNCALIBRATED =
303        "android.sensor.gyroscope_uncalibrated";
304
305    /**
306     * A constant describing a significant motion trigger sensor.
307     * <p>
308     * It triggers when an event occurs and then automatically disables
309     * itself. The sensor continues to operate while the device is asleep
310     * and will automatically wake the device to notify when significant
311     * motion is detected. The application does not need to hold any wake
312     * locks for this sensor to trigger. This is a wake up sensor.
313     * <p>See {@link TriggerEvent} for more details.
314     *
315     * @see #isWakeUpSensor()
316     */
317    public static final int TYPE_SIGNIFICANT_MOTION = 17;
318
319    /**
320     * A constant string describing a significant motion trigger sensor.
321     *
322     * @see #TYPE_SIGNIFICANT_MOTION
323     */
324    public static final String STRING_TYPE_SIGNIFICANT_MOTION =
325        "android.sensor.significant_motion";
326
327    /**
328     * A constant describing a step detector sensor.
329     * <p>
330     * A sensor of this type triggers an event each time a step is taken by the user. The only
331     * allowed value to return is 1.0 and an event is generated for each step. Like with any other
332     * event, the timestamp indicates when the event (here the step) occurred, this corresponds to
333     * when the foot hit the ground, generating a high variation in acceleration. This sensor is
334     * only for detecting every individual step as soon as it is taken, for example to perform dead
335     * reckoning. If you only need aggregate number of steps taken over a period of time, register
336     * for {@link #TYPE_STEP_COUNTER} instead. It is defined as a
337     * {@link Sensor#REPORTING_MODE_SPECIAL_TRIGGER} sensor.
338     * <p>
339     * See {@link android.hardware.SensorEvent#values SensorEvent.values} for more details.
340     */
341    public static final int TYPE_STEP_DETECTOR = 18;
342
343    /**
344     * A constant string describing a step detector sensor.
345     *
346     * @see #TYPE_STEP_DETECTOR
347     */
348    public static final String STRING_TYPE_STEP_DETECTOR = "android.sensor.step_detector";
349
350    /**
351     * A constant describing a step counter sensor.
352     * <p>
353     * A sensor of this type returns the number of steps taken by the user since the last reboot
354     * while activated. The value is returned as a float (with the fractional part set to zero) and
355     * is reset to zero only on a system reboot. The timestamp of the event is set to the time when
356     * the last step for that event was taken. This sensor is implemented in hardware and is
357     * expected to be low power. If you want to continuously track the number of steps over a long
358     * period of time, do NOT unregister for this sensor, so that it keeps counting steps in the
359     * background even when the AP is in suspend mode and report the aggregate count when the AP
360     * is awake. Application needs to stay registered for this sensor because step counter does not
361     * count steps if it is not activated. This sensor is ideal for fitness tracking applications.
362     * It is defined as an {@link Sensor#REPORTING_MODE_ON_CHANGE} sensor.
363     * <p>
364     * See {@link android.hardware.SensorEvent#values SensorEvent.values} for more details.
365     */
366    public static final int TYPE_STEP_COUNTER = 19;
367
368    /**
369     * A constant string describing a step counter sensor.
370     *
371     * @see #TYPE_STEP_COUNTER
372     */
373    public static final String STRING_TYPE_STEP_COUNTER = "android.sensor.step_counter";
374
375    /**
376     * A constant describing a geo-magnetic rotation vector.
377     * <p>
378     * Similar to {@link #TYPE_ROTATION_VECTOR}, but using a magnetometer instead of using a
379     * gyroscope. This sensor uses lower power than the other rotation vectors, because it doesn't
380     * use the gyroscope. However, it is more noisy and will work best outdoors.
381     * <p>
382     * See {@link android.hardware.SensorEvent#values SensorEvent.values} for more details.
383     */
384    public static final int TYPE_GEOMAGNETIC_ROTATION_VECTOR = 20;
385
386    /**
387     * A constant string describing a geo-magnetic rotation vector.
388     *
389     * @see #TYPE_GEOMAGNETIC_ROTATION_VECTOR
390     */
391    public static final String STRING_TYPE_GEOMAGNETIC_ROTATION_VECTOR =
392        "android.sensor.geomagnetic_rotation_vector";
393
394    /**
395     * A constant describing a heart rate monitor.
396     * <p>
397     * The reported value is the heart rate in beats per minute.
398     * <p>
399     * The reported accuracy represents the status of the monitor during the reading. See the
400     * {@code SENSOR_STATUS_*} constants in {@link android.hardware.SensorManager SensorManager}
401     * for more details on accuracy/status values. In particular, when the accuracy is
402     * {@code SENSOR_STATUS_UNRELIABLE} or {@code SENSOR_STATUS_NO_CONTACT}, the heart rate
403     * value should be discarded.
404     * <p>
405     * This sensor requires permission {@code android.permission.BODY_SENSORS}.
406     * It will not be returned by {@code SensorManager.getSensorsList} nor
407     * {@code SensorManager.getDefaultSensor} if the application doesn't have this permission.
408     */
409    public static final int TYPE_HEART_RATE = 21;
410
411    /**
412     * A constant string describing a heart rate monitor.
413     *
414     * @see #TYPE_HEART_RATE
415     */
416    public static final String STRING_TYPE_HEART_RATE = "android.sensor.heart_rate";
417
418    /**
419     * A sensor of this type generates an event each time a tilt event is detected. A tilt event
420     * is generated if the direction of the 2-seconds window average gravity changed by at
421     * least 35 degrees since the activation of the sensor. It is a wake up sensor.
422     *
423     * @hide
424     * @see #isWakeUpSensor()
425     */
426    public static final int TYPE_TILT_DETECTOR = 22;
427
428    /**
429     * A constant string describing a wake up tilt detector sensor type.
430     *
431     * @hide
432     * @see #TYPE_WAKE_UP_TILT_DETECTOR
433     */
434    public static final String SENSOR_STRING_TYPE_TILT_DETECTOR =
435            "android.sensor.tilt_detector";
436
437    /**
438     * A constant describing a wake gesture sensor.
439     * <p>
440     * Wake gesture sensors enable waking up the device based on a device specific motion.
441     * <p>
442     * When this sensor triggers, the device behaves as if the power button was pressed, turning the
443     * screen on. This behavior (turning on the screen when this sensor triggers) might be
444     * deactivated by the user in the device settings. Changes in settings do not impact the
445     * behavior of the sensor: only whether the framework turns the screen on when it triggers.
446     * <p>
447     * The actual gesture to be detected is not specified, and can be chosen by the manufacturer of
448     * the device. This sensor must be low power, as it is likely to be activated 24/7.
449     * Values of events created by this sensors should not be used.
450     *
451     * @see #isWakeUpSensor()
452     * @hide This sensor is expected to only be used by the system ui
453     */
454    public static final int TYPE_WAKE_GESTURE = 23;
455
456    /**
457     * A constant string describing a wake gesture sensor.
458     *
459     * @hide This sensor is expected to only be used by the system ui
460     * @see #TYPE_WAKE_GESTURE
461     */
462    public static final String STRING_TYPE_WAKE_GESTURE = "android.sensor.wake_gesture";
463
464    /**
465     * A constant describing a wake gesture sensor.
466     * <p>
467     * A sensor enabling briefly turning the screen on to enable the user to
468     * glance content on screen based on a specific motion.  The device should
469     * turn the screen off after a few moments.
470     * <p>
471     * When this sensor triggers, the device turns the screen on momentarily
472     * to allow the user to glance notifications or other content while the
473     * device remains locked in a non-interactive state (dozing). This behavior
474     * (briefly turning on the screen when this sensor triggers) might be deactivated
475     * by the user in the device settings. Changes in settings do not impact the
476     * behavior of the sensor: only whether the framework briefly turns the screen on
477     * when it triggers.
478     * <p>
479     * The actual gesture to be detected is not specified, and can be chosen by the manufacturer of
480     * the device. This sensor must be low power, as it is likely to be activated 24/7.
481     * Values of events created by this sensors should not be used.
482     *
483     * @see #isWakeUpSensor()
484     * @hide This sensor is expected to only be used by the system ui
485     */
486    public static final int TYPE_GLANCE_GESTURE = 24;
487
488    /**
489     * A constant string describing a wake gesture sensor.
490     *
491     * @hide This sensor is expected to only be used by the system ui
492     * @see #TYPE_GLANCE_GESTURE
493     */
494    public static final String STRING_TYPE_GLANCE_GESTURE = "android.sensor.glance_gesture";
495
496     /**
497     * A constant describing a pick up sensor.
498     *
499     * A sensor of this type triggers when the device is picked up regardless of wherever it was
500     * before (desk, pocket, bag). The only allowed return value is 1.0. This sensor deactivates
501     * itself immediately after it triggers.
502     *
503     * @hide Expected to be used internally for always on display.
504     */
505    public static final int TYPE_PICK_UP_GESTURE = 25;
506
507    /**
508     * A constant string describing a pick up sensor.
509     *
510     * @hide This sensor is expected to be used internally for always on display.
511     * @see #TYPE_PICK_UP_GESTURE
512     */
513    public static final String STRING_TYPE_PICK_UP_GESTURE = "android.sensor.pick_up_gesture";
514
515     /**
516     * A constant describing a wrist tilt gesture sensor.
517     *
518     * A sensor of this type triggers when the device face is tilted towards the user.
519     * The only allowed return value is 1.0.
520     * This sensor remains active until disabled.
521     *
522     * @hide This sensor is expected to only be used by the system ui
523     */
524    @SystemApi
525    public static final int TYPE_WRIST_TILT_GESTURE = 26;
526
527    /**
528     * A constant string describing a wrist tilt gesture sensor.
529     *
530     * @hide This sensor is expected to only be used by the system ui
531     * @see #TYPE_WRIST_TILT_GESTURE
532     */
533    @SystemApi
534    public static final String STRING_TYPE_WRIST_TILT_GESTURE = "android.sensor.wrist_tilt_gesture";
535
536    /**
537     * A constant describing all sensor types.
538     */
539    public static final int TYPE_ALL = -1;
540
541    // If this flag is set, the sensor defined as a wake up sensor. This field and REPORTING_MODE_*
542    // constants are defined as flags in sensors.h. Modify at both places if needed.
543    private static final int SENSOR_FLAG_WAKE_UP_SENSOR = 1;
544
545    /**
546     * Events are reported at a constant rate which is set by the rate parameter of
547     * {@link SensorManager#registerListener(SensorEventListener, Sensor, int)}. Note: If other
548     * applications are requesting a higher rate, the sensor data might be delivered at faster rates
549     * than requested.
550     */
551    public static final int REPORTING_MODE_CONTINUOUS = 0;
552
553    /**
554     * Events are reported only when the value changes. Event delivery rate can be limited by
555     * setting appropriate value for rate parameter of
556     * {@link SensorManager#registerListener(SensorEventListener, Sensor, int)} Note: If other
557     * applications are requesting a higher rate, the sensor data might be delivered at faster rates
558     * than requested.
559     */
560    public static final int REPORTING_MODE_ON_CHANGE = 1;
561
562    /**
563     * Events are reported in one-shot mode. Upon detection of an event, the sensor deactivates
564     * itself and then sends a single event. Sensors of this reporting mode must be registered to
565     * using {@link SensorManager#requestTriggerSensor(TriggerEventListener, Sensor)}.
566     */
567    public static final int REPORTING_MODE_ONE_SHOT = 2;
568
569    /**
570     * Events are reported as described in the description of the sensor. The rate passed to
571     * registerListener might not have an impact on the rate of event delivery. See the sensor
572     * definition for more information on when and how frequently the events are reported. For
573     * example, step detectors report events when a step is detected.
574     *
575     * @see SensorManager#registerListener(SensorEventListener, Sensor, int, int)
576     */
577    public static final int REPORTING_MODE_SPECIAL_TRIGGER = 3;
578
579    // Mask for the LSB 2nd, 3rd and fourth bits.
580    private static final int REPORTING_MODE_MASK = 0xE;
581    private static final int REPORTING_MODE_SHIFT = 1;
582
583    // MASK for LSB fifth bit. Used to know whether the sensor supports data injection or not.
584    private static final int DATA_INJECTION_MASK = 0x10;
585    private static final int DATA_INJECTION_SHIFT = 4;
586
587    // TODO(): The following arrays are fragile and error-prone. This needs to be refactored.
588
589    // Note: This needs to be updated, whenever a new sensor is added.
590    // Holds the reporting mode and maximum length of the values array
591    // associated with
592    // {@link SensorEvent} or {@link TriggerEvent} for the Sensor
593    private static final int[] sSensorReportingModes = {
594            0, // padding because sensor types start at 1
595            3, // SENSOR_TYPE_ACCELEROMETER
596            3, // SENSOR_TYPE_GEOMAGNETIC_FIELD
597            3, // SENSOR_TYPE_ORIENTATION
598            3, // SENSOR_TYPE_GYROSCOPE
599            3, // SENSOR_TYPE_LIGHT
600            3, // SENSOR_TYPE_PRESSURE
601            3, // SENSOR_TYPE_TEMPERATURE
602            3, // SENSOR_TYPE_PROXIMITY
603            3, // SENSOR_TYPE_GRAVITY
604            3, // SENSOR_TYPE_LINEAR_ACCELERATION
605            5, // SENSOR_TYPE_ROTATION_VECTOR
606            3, // SENSOR_TYPE_RELATIVE_HUMIDITY
607            3, // SENSOR_TYPE_AMBIENT_TEMPERATURE
608            6, // SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED
609            4, // SENSOR_TYPE_GAME_ROTATION_VECTOR
610            6, // SENSOR_TYPE_GYROSCOPE_UNCALIBRATED
611            1, // SENSOR_TYPE_SIGNIFICANT_MOTION
612            1, // SENSOR_TYPE_STEP_DETECTOR
613            1, // SENSOR_TYPE_STEP_COUNTER
614            5, // SENSOR_TYPE_GEOMAGNETIC_ROTATION_VECTOR
615            1, // SENSOR_TYPE_HEART_RATE_MONITOR
616            1, // SENSOR_TYPE_WAKE_UP_TILT_DETECTOR
617            1, // SENSOR_TYPE_WAKE_GESTURE
618            1, // SENSOR_TYPE_GLANCE_GESTURE
619            1, // SENSOR_TYPE_PICK_UP_GESTURE
620            1, // SENSOR_TYPE_WRIST_TILT_GESTURE
621    };
622
623    /**
624     * Each sensor has exactly one reporting mode associated with it. This method returns the
625     * reporting mode constant for this sensor type.
626     *
627     * @return Reporting mode for the input sensor, one of REPORTING_MODE_* constants.
628     * @see #REPORTING_MODE_CONTINUOUS
629     * @see #REPORTING_MODE_ON_CHANGE
630     * @see #REPORTING_MODE_ONE_SHOT
631     * @see #REPORTING_MODE_SPECIAL_TRIGGER
632     */
633    public int getReportingMode() {
634        return ((mFlags & REPORTING_MODE_MASK) >> REPORTING_MODE_SHIFT);
635    }
636
637    static int getMaxLengthValuesArray(Sensor sensor, int sdkLevel) {
638        // RotationVector length has changed to 3 to 5 for API level 18
639        // Set it to 3 for backward compatibility.
640        if (sensor.mType == Sensor.TYPE_ROTATION_VECTOR &&
641                sdkLevel <= Build.VERSION_CODES.JELLY_BEAN_MR1) {
642            return 3;
643        }
644        int offset = sensor.mType;
645        if (offset >= sSensorReportingModes.length) {
646            // we don't know about this sensor, so this is probably a
647            // vendor-defined sensor, in that case, we don't know how many value
648            // it has
649            // so we return the maximum and assume the app will know.
650            // FIXME: sensor HAL should advertise how much data is returned per
651            // sensor
652            return 16;
653        }
654        return sSensorReportingModes[offset];
655    }
656
657    /* Some of these fields are set only by the native bindings in
658     * SensorManager.
659     */
660    private String  mName;
661    private String  mVendor;
662    private int     mVersion;
663    private int     mHandle;
664    private int     mType;
665    private float   mMaxRange;
666    private float   mResolution;
667    private float   mPower;
668    private int     mMinDelay;
669    private int     mFifoReservedEventCount;
670    private int     mFifoMaxEventCount;
671    private String  mStringType;
672    private String  mRequiredPermission;
673    private int     mMaxDelay;
674    private int     mFlags;
675
676    Sensor() {
677    }
678
679    /**
680     * @return name string of the sensor.
681     */
682    public String getName() {
683        return mName;
684    }
685
686    /**
687     * @return vendor string of this sensor.
688     */
689    public String getVendor() {
690        return mVendor;
691    }
692
693    /**
694     * @return generic type of this sensor.
695     */
696    public int getType() {
697        return mType;
698    }
699
700    /**
701     * @return version of the sensor's module.
702     */
703    public int getVersion() {
704        return mVersion;
705    }
706
707    /**
708     * @return maximum range of the sensor in the sensor's unit.
709     */
710    public float getMaximumRange() {
711        return mMaxRange;
712    }
713
714    /**
715     * @return resolution of the sensor in the sensor's unit.
716     */
717    public float getResolution() {
718        return mResolution;
719    }
720
721    /**
722     * @return the power in mA used by this sensor while in use
723     */
724    public float getPower() {
725        return mPower;
726    }
727
728    /**
729     * @return the minimum delay allowed between two events in microsecond
730     * or zero if this sensor only returns a value when the data it's measuring
731     * changes.
732     */
733    public int getMinDelay() {
734        return mMinDelay;
735    }
736
737    /**
738     * @return Number of events reserved for this sensor in the batch mode FIFO. This gives a
739     * guarantee on the minimum number of events that can be batched.
740     */
741    public int getFifoReservedEventCount() {
742        return mFifoReservedEventCount;
743    }
744
745    /**
746     * @return Maximum number of events of this sensor that could be batched. If this value is zero
747     * it indicates that batch mode is not supported for this sensor. If other applications
748     * registered to batched sensors, the actual number of events that can be batched might be
749     * smaller because the hardware FiFo will be partially used to batch the other sensors.
750     */
751    public int getFifoMaxEventCount() {
752        return mFifoMaxEventCount;
753    }
754
755    /**
756     * @return The type of this sensor as a string.
757     */
758    public String getStringType() {
759        return mStringType;
760    }
761
762    /**
763     * @hide
764     * @return The permission required to access this sensor. If empty, no permission is required.
765     */
766    public String getRequiredPermission() {
767        return mRequiredPermission;
768    }
769
770    /** @hide */
771    public int getHandle() {
772        return mHandle;
773    }
774
775    /**
776     * This value is defined only for continuous and on-change sensors. It is the delay between two
777     * sensor events corresponding to the lowest frequency that this sensor supports. When lower
778     * frequencies are requested through registerListener() the events will be generated at this
779     * frequency instead. It can be used to estimate when the batch FIFO may be full. Older devices
780     * may set this value to zero. Ignore this value in case it is negative or zero.
781     *
782     * @return The max delay for this sensor in microseconds.
783     */
784    public int getMaxDelay() {
785        return mMaxDelay;
786    }
787
788    /**
789     * Returns true if the sensor is a wake-up sensor.
790     * <p>
791     * <b>Application Processor Power modes</b> <p>
792     * Application Processor(AP), is the processor on which applications run.  When no wake lock is held
793     * and the user is not interacting with the device, this processor can enter a “Suspend” mode,
794     * reducing the power consumption by 10 times or more.
795     * </p>
796     * <p>
797     * <b>Non-wake-up sensors</b> <p>
798     * Non-wake-up sensors are sensors that do not wake the AP out of suspend to report data. While
799     * the AP is in suspend mode, the sensors continue to function and generate events, which are
800     * put in a hardware FIFO. The events in the FIFO are delivered to the application when the AP
801     * wakes up. If the FIFO was too small to store all events generated while the AP was in
802     * suspend mode, the older events are lost: the oldest data is dropped to accommodate the newer
803     * data. In the extreme case where the FIFO is non-existent {@code maxFifoEventCount() == 0},
804     * all events generated while the AP was in suspend mode are lost. Applications using
805     * non-wake-up sensors should usually:
806     * <ul>
807     * <li>Either unregister from the sensors when they do not need them, usually in the activity’s
808     * {@code onPause} method. This is the most common case.
809     * <li>Or realize that the sensors are consuming some power while the AP is in suspend mode and
810     * that even then, some events might be lost.
811     * </ul>
812     * </p>
813     * <p>
814     * <b>Wake-up sensors</b> <p>
815     * In opposition to non-wake-up sensors, wake-up sensors ensure that their data is delivered
816     * independently of the state of the AP. While the AP is awake, the wake-up sensors behave
817     * like non-wake-up-sensors. When the AP is asleep, wake-up sensors wake up the AP to deliver
818     * events. That is, the AP will wake up and the sensor will deliver the events before the
819     * maximum reporting latency is elapsed or the hardware FIFO gets full. See {@link
820     * SensorManager#registerListener(SensorEventListener, Sensor, int, int)} for more details.
821     * </p>
822     *
823     * @return <code>true</code> if this is a wake-up sensor, <code>false</code> otherwise.
824     */
825    public boolean isWakeUpSensor() {
826        return (mFlags & SENSOR_FLAG_WAKE_UP_SENSOR) != 0;
827    }
828
829    /**
830     * Returns true if the sensor supports data injection when the
831     * HAL is set to data injection mode.
832     *
833     * @return <code>true</code> if the sensor supports data
834     *         injection when the HAL is set in injection mode,
835     *         false otherwise.
836     * @hide
837     */
838    @SystemApi
839    public boolean isDataInjectionSupported() {
840        return (((mFlags & DATA_INJECTION_MASK) >> DATA_INJECTION_SHIFT)) != 0;
841    }
842
843    void setRange(float max, float res) {
844        mMaxRange = max;
845        mResolution = res;
846    }
847
848    @Override
849    public String toString() {
850        return "{Sensor name=\"" + mName + "\", vendor=\"" + mVendor + "\", version=" + mVersion
851                + ", type=" + mType + ", maxRange=" + mMaxRange + ", resolution=" + mResolution
852                + ", power=" + mPower + ", minDelay=" + mMinDelay + "}";
853    }
854
855    /**
856     * Sets the Type associated with the sensor.
857     * NOTE: to be used only by native bindings in SensorManager.
858     *
859     * This allows interned static strings to be used across all representations of the Sensor. If
860     * a sensor type is not referenced here, it will still be interned by the native SensorManager.
861     *
862     * @return {@code true} if the StringType was successfully set, {@code false} otherwise.
863     */
864    private boolean setType(int value) {
865        mType = value;
866        switch (mType) {
867            case TYPE_ACCELEROMETER:
868                mStringType = STRING_TYPE_ACCELEROMETER;
869                return true;
870            case TYPE_AMBIENT_TEMPERATURE:
871                mStringType = STRING_TYPE_AMBIENT_TEMPERATURE;
872                return true;
873            case TYPE_GAME_ROTATION_VECTOR:
874                mStringType = STRING_TYPE_GAME_ROTATION_VECTOR;
875                return true;
876            case TYPE_GEOMAGNETIC_ROTATION_VECTOR:
877                mStringType = STRING_TYPE_GEOMAGNETIC_ROTATION_VECTOR;
878                return true;
879            case TYPE_GLANCE_GESTURE:
880                mStringType = STRING_TYPE_GLANCE_GESTURE;
881                return true;
882            case TYPE_GRAVITY:
883                mStringType = STRING_TYPE_GRAVITY;
884                return true;
885            case TYPE_GYROSCOPE:
886                mStringType = STRING_TYPE_GYROSCOPE;
887                return true;
888            case TYPE_GYROSCOPE_UNCALIBRATED:
889                mStringType = STRING_TYPE_GYROSCOPE_UNCALIBRATED;
890                return true;
891            case TYPE_HEART_RATE:
892                mStringType = STRING_TYPE_HEART_RATE;
893                return true;
894            case TYPE_LIGHT:
895                mStringType = STRING_TYPE_LIGHT;
896                return true;
897            case TYPE_LINEAR_ACCELERATION:
898                mStringType = STRING_TYPE_LINEAR_ACCELERATION;
899                return true;
900            case TYPE_MAGNETIC_FIELD:
901                mStringType = STRING_TYPE_MAGNETIC_FIELD;
902                return true;
903            case TYPE_MAGNETIC_FIELD_UNCALIBRATED:
904                mStringType = STRING_TYPE_MAGNETIC_FIELD_UNCALIBRATED;
905                return true;
906            case TYPE_PICK_UP_GESTURE:
907                mStringType = STRING_TYPE_PICK_UP_GESTURE;
908                return true;
909            case TYPE_PRESSURE:
910                mStringType = STRING_TYPE_PRESSURE;
911                return true;
912            case TYPE_PROXIMITY:
913                mStringType = STRING_TYPE_PROXIMITY;
914                return true;
915            case TYPE_RELATIVE_HUMIDITY:
916                mStringType = STRING_TYPE_RELATIVE_HUMIDITY;
917                return true;
918            case TYPE_ROTATION_VECTOR:
919                mStringType = STRING_TYPE_ROTATION_VECTOR;
920                return true;
921            case TYPE_SIGNIFICANT_MOTION:
922                mStringType = STRING_TYPE_SIGNIFICANT_MOTION;
923                return true;
924            case TYPE_STEP_COUNTER:
925                mStringType = STRING_TYPE_STEP_COUNTER;
926                return true;
927            case TYPE_STEP_DETECTOR:
928                mStringType = STRING_TYPE_STEP_DETECTOR;
929                return true;
930            case TYPE_TILT_DETECTOR:
931                mStringType = SENSOR_STRING_TYPE_TILT_DETECTOR;
932                return true;
933            case TYPE_WAKE_GESTURE:
934                mStringType = STRING_TYPE_WAKE_GESTURE;
935                return true;
936            case TYPE_ORIENTATION:
937                mStringType = STRING_TYPE_ORIENTATION;
938                return true;
939            case TYPE_TEMPERATURE:
940                mStringType = STRING_TYPE_TEMPERATURE;
941                return true;
942            default:
943                return false;
944        }
945    }
946}
947