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 
18 package android.hardware;
19 
20 import android.os.Build;
21 import 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  */
32 public 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      */
getReportingMode()633     public int getReportingMode() {
634         return ((mFlags & REPORTING_MODE_MASK) >> REPORTING_MODE_SHIFT);
635     }
636 
getMaxLengthValuesArray(Sensor sensor, int sdkLevel)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 
Sensor()676     Sensor() {
677     }
678 
679     /**
680      * @return name string of the sensor.
681      */
getName()682     public String getName() {
683         return mName;
684     }
685 
686     /**
687      * @return vendor string of this sensor.
688      */
getVendor()689     public String getVendor() {
690         return mVendor;
691     }
692 
693     /**
694      * @return generic type of this sensor.
695      */
getType()696     public int getType() {
697         return mType;
698     }
699 
700     /**
701      * @return version of the sensor's module.
702      */
getVersion()703     public int getVersion() {
704         return mVersion;
705     }
706 
707     /**
708      * @return maximum range of the sensor in the sensor's unit.
709      */
getMaximumRange()710     public float getMaximumRange() {
711         return mMaxRange;
712     }
713 
714     /**
715      * @return resolution of the sensor in the sensor's unit.
716      */
getResolution()717     public float getResolution() {
718         return mResolution;
719     }
720 
721     /**
722      * @return the power in mA used by this sensor while in use
723      */
getPower()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      */
getMinDelay()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      */
getFifoReservedEventCount()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      */
getFifoMaxEventCount()751     public int getFifoMaxEventCount() {
752         return mFifoMaxEventCount;
753     }
754 
755     /**
756      * @return The type of this sensor as a string.
757      */
getStringType()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      */
getRequiredPermission()766     public String getRequiredPermission() {
767         return mRequiredPermission;
768     }
769 
770     /** @hide */
getHandle()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      */
getMaxDelay()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      */
isWakeUpSensor()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
isDataInjectionSupported()839     public boolean isDataInjectionSupported() {
840         return (((mFlags & DATA_INJECTION_MASK) >> DATA_INJECTION_SHIFT)) != 0;
841     }
842 
setRange(float max, float res)843     void setRange(float max, float res) {
844         mMaxRange = max;
845         mResolution = res;
846     }
847 
848     @Override
toString()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      */
setType(int value)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