1 /*
2  * Copyright (C) 2007 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 package android.location;
18 
19 import android.annotation.SystemApi;
20 import android.annotation.TestApi;
21 import android.compat.annotation.UnsupportedAppUsage;
22 import android.os.Build;
23 import android.os.Bundle;
24 import android.os.Parcel;
25 import android.os.Parcelable;
26 import android.os.SystemClock;
27 import android.util.Printer;
28 import android.util.TimeUtils;
29 
30 import java.text.DecimalFormat;
31 import java.util.StringTokenizer;
32 
33 /**
34  * A data class representing a geographic location.
35  *
36  * <p>A location can consist of a latitude, longitude, timestamp,
37  * and other information such as bearing, altitude and velocity.
38  *
39  * <p>All locations generated by the {@link LocationManager} are
40  * guaranteed to have a valid latitude, longitude, and timestamp
41  * (both UTC time and elapsed real-time since boot), all other
42  * parameters are optional.
43  */
44 public class Location implements Parcelable {
45     /**
46      * Constant used to specify formatting of a latitude or longitude
47      * in the form "[+-]DDD.DDDDD where D indicates degrees.
48      */
49     public static final int FORMAT_DEGREES = 0;
50 
51     /**
52      * Constant used to specify formatting of a latitude or longitude
53      * in the form "[+-]DDD:MM.MMMMM" where D indicates degrees and
54      * M indicates minutes of arc (1 minute = 1/60th of a degree).
55      */
56     public static final int FORMAT_MINUTES = 1;
57 
58     /**
59      * Constant used to specify formatting of a latitude or longitude
60      * in the form "DDD:MM:SS.SSSSS" where D indicates degrees, M
61      * indicates minutes of arc, and S indicates seconds of arc (1
62      * minute = 1/60th of a degree, 1 second = 1/3600th of a degree).
63      */
64     public static final int FORMAT_SECONDS = 2;
65 
66     /**
67      * Bundle key for a version of the location that has been fed through
68      * LocationFudger. Allows location providers to flag locations as being
69      * safe for use with ACCESS_COARSE_LOCATION permission.
70      *
71      * @hide
72      */
73     public static final String EXTRA_COARSE_LOCATION = "coarseLocation";
74 
75     /**
76      * Bundle key for a version of the location containing no GPS data.
77      * Allows location providers to flag locations as being safe to
78      * feed to LocationFudger.
79      *
80      * @hide
81      */
82     public static final String EXTRA_NO_GPS_LOCATION = "noGPSLocation";
83 
84     /**
85      * Bit mask for mFieldsMask indicating the presence of mAltitude.
86      */
87     private static final int HAS_ALTITUDE_MASK = 1;
88     /**
89      * Bit mask for mFieldsMask indicating the presence of mSpeed.
90      */
91     private static final int HAS_SPEED_MASK = 2;
92     /**
93      * Bit mask for mFieldsMask indicating the presence of mBearing.
94      */
95     private static final int HAS_BEARING_MASK = 4;
96     /**
97      * Bit mask for mFieldsMask indicating the presence of mHorizontalAccuracy.
98      */
99     private static final int HAS_HORIZONTAL_ACCURACY_MASK = 8;
100     /**
101      * Bit mask for mFieldsMask indicating location is from a mock provider.
102      */
103     private static final int HAS_MOCK_PROVIDER_MASK = 16;
104     /**
105      * Bit mask for mFieldsMask indicating the presence of mVerticalAccuracy.
106      */
107     private static final int HAS_VERTICAL_ACCURACY_MASK = 32;
108     /**
109      * Bit mask for mFieldsMask indicating the presence of mSpeedAccuracy.
110      */
111     private static final int HAS_SPEED_ACCURACY_MASK = 64;
112     /**
113      * Bit mask for mFieldsMask indicating the presence of mBearingAccuracy.
114      */
115     private static final int HAS_BEARING_ACCURACY_MASK = 128;
116     /**
117      * Bit mask for mFieldsMask indicating the presence of mElapsedRealtimeUncertaintyNanos.
118      */
119     private static final int HAS_ELAPSED_REALTIME_UNCERTAINTY_MASK = 256;
120 
121     // Cached data to make bearing/distance computations more efficient for the case
122     // where distanceTo and bearingTo are called in sequence.  Assume this typically happens
123     // on the same thread for caching purposes.
124     private static ThreadLocal<BearingDistanceCache> sBearingDistanceCache
125             = new ThreadLocal<BearingDistanceCache>() {
126         @Override
127         protected BearingDistanceCache initialValue() {
128             return new BearingDistanceCache();
129         }
130     };
131 
132     @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
133     private String mProvider;
134     private long mTime = 0;
135     @UnsupportedAppUsage
136     private long mElapsedRealtimeNanos = 0;
137     // Estimate of the relative precision of the alignment of this SystemClock
138     // timestamp, with the reported measurements in nanoseconds (68% confidence).
139     private double mElapsedRealtimeUncertaintyNanos = 0.0f;
140     private double mLatitude = 0.0;
141     private double mLongitude = 0.0;
142     private double mAltitude = 0.0f;
143     private float mSpeed = 0.0f;
144     private float mBearing = 0.0f;
145     private float mHorizontalAccuracyMeters = 0.0f;
146     private float mVerticalAccuracyMeters = 0.0f;
147     private float mSpeedAccuracyMetersPerSecond = 0.0f;
148     private float mBearingAccuracyDegrees = 0.0f;
149 
150     private Bundle mExtras = null;
151 
152     // A bitmask of fields present in this object (see HAS_* constants defined above).
153     private int mFieldsMask = 0;
154 
155     /**
156      * Construct a new Location with a named provider.
157      *
158      * <p>By default time, latitude and longitude are 0, and the location
159      * has no bearing, altitude, speed, accuracy or extras.
160      *
161      * @param provider the source that provides the location. It can be of type
162      * {@link LocationManager#GPS_PROVIDER}, {@link LocationManager#NETWORK_PROVIDER},
163      * or {@link LocationManager#PASSIVE_PROVIDER}. You can also define your own
164      * provider string, in which case an empty string is a valid provider.
165      */
Location(String provider)166     public Location(String provider) {
167         mProvider = provider;
168     }
169 
170     /**
171      * Construct a new Location object that is copied from an existing one.
172      */
Location(Location l)173     public Location(Location l) {
174         set(l);
175     }
176 
177     /**
178      * Sets the contents of the location to the values from the given location.
179      */
set(Location l)180     public void set(Location l) {
181         mProvider = l.mProvider;
182         mTime = l.mTime;
183         mElapsedRealtimeNanos = l.mElapsedRealtimeNanos;
184         mElapsedRealtimeUncertaintyNanos = l.mElapsedRealtimeUncertaintyNanos;
185         mFieldsMask = l.mFieldsMask;
186         mLatitude = l.mLatitude;
187         mLongitude = l.mLongitude;
188         mAltitude = l.mAltitude;
189         mSpeed = l.mSpeed;
190         mBearing = l.mBearing;
191         mHorizontalAccuracyMeters = l.mHorizontalAccuracyMeters;
192         mVerticalAccuracyMeters = l.mVerticalAccuracyMeters;
193         mSpeedAccuracyMetersPerSecond = l.mSpeedAccuracyMetersPerSecond;
194         mBearingAccuracyDegrees = l.mBearingAccuracyDegrees;
195         mExtras = (l.mExtras == null) ? null : new Bundle(l.mExtras);
196     }
197 
198     /**
199      * Clears the contents of the location.
200      */
reset()201     public void reset() {
202         mProvider = null;
203         mTime = 0;
204         mElapsedRealtimeNanos = 0;
205         mElapsedRealtimeUncertaintyNanos = 0.0;
206         mFieldsMask = 0;
207         mLatitude = 0;
208         mLongitude = 0;
209         mAltitude = 0;
210         mSpeed = 0;
211         mBearing = 0;
212         mHorizontalAccuracyMeters = 0;
213         mVerticalAccuracyMeters = 0;
214         mSpeedAccuracyMetersPerSecond = 0;
215         mBearingAccuracyDegrees = 0;
216         mExtras = null;
217     }
218 
219     /**
220      * Converts a coordinate to a String representation. The outputType
221      * may be one of FORMAT_DEGREES, FORMAT_MINUTES, or FORMAT_SECONDS.
222      * The coordinate must be a valid double between -180.0 and 180.0.
223      * This conversion is performed in a method that is dependent on the
224      * default locale, and so is not guaranteed to round-trip with
225      * {@link #convert(String)}.
226      *
227      * @throws IllegalArgumentException if coordinate is less than
228      * -180.0, greater than 180.0, or is not a number.
229      * @throws IllegalArgumentException if outputType is not one of
230      * FORMAT_DEGREES, FORMAT_MINUTES, or FORMAT_SECONDS.
231      */
convert(double coordinate, int outputType)232     public static String convert(double coordinate, int outputType) {
233         if (coordinate < -180.0 || coordinate > 180.0 ||
234             Double.isNaN(coordinate)) {
235             throw new IllegalArgumentException("coordinate=" + coordinate);
236         }
237         if ((outputType != FORMAT_DEGREES) &&
238             (outputType != FORMAT_MINUTES) &&
239             (outputType != FORMAT_SECONDS)) {
240             throw new IllegalArgumentException("outputType=" + outputType);
241         }
242 
243         StringBuilder sb = new StringBuilder();
244 
245         // Handle negative values
246         if (coordinate < 0) {
247             sb.append('-');
248             coordinate = -coordinate;
249         }
250 
251         DecimalFormat df = new DecimalFormat("###.#####");
252         if (outputType == FORMAT_MINUTES || outputType == FORMAT_SECONDS) {
253             int degrees = (int) Math.floor(coordinate);
254             sb.append(degrees);
255             sb.append(':');
256             coordinate -= degrees;
257             coordinate *= 60.0;
258             if (outputType == FORMAT_SECONDS) {
259                 int minutes = (int) Math.floor(coordinate);
260                 sb.append(minutes);
261                 sb.append(':');
262                 coordinate -= minutes;
263                 coordinate *= 60.0;
264             }
265         }
266         sb.append(df.format(coordinate));
267         return sb.toString();
268     }
269 
270     /**
271      * Converts a String in one of the formats described by
272      * FORMAT_DEGREES, FORMAT_MINUTES, or FORMAT_SECONDS into a
273      * double. This conversion is performed in a locale agnostic
274      * method, and so is not guaranteed to round-trip with
275      * {@link #convert(double, int)}.
276      *
277      * @throws NullPointerException if coordinate is null
278      * @throws IllegalArgumentException if the coordinate is not
279      * in one of the valid formats.
280      */
convert(String coordinate)281     public static double convert(String coordinate) {
282         // IllegalArgumentException if bad syntax
283         if (coordinate == null) {
284             throw new NullPointerException("coordinate");
285         }
286 
287         boolean negative = false;
288         if (coordinate.charAt(0) == '-') {
289             coordinate = coordinate.substring(1);
290             negative = true;
291         }
292 
293         StringTokenizer st = new StringTokenizer(coordinate, ":");
294         int tokens = st.countTokens();
295         if (tokens < 1) {
296             throw new IllegalArgumentException("coordinate=" + coordinate);
297         }
298         try {
299             String degrees = st.nextToken();
300             double val;
301             if (tokens == 1) {
302                 val = Double.parseDouble(degrees);
303                 return negative ? -val : val;
304             }
305 
306             String minutes = st.nextToken();
307             int deg = Integer.parseInt(degrees);
308             double min;
309             double sec = 0.0;
310             boolean secPresent = false;
311 
312             if (st.hasMoreTokens()) {
313                 min = Integer.parseInt(minutes);
314                 String seconds = st.nextToken();
315                 sec = Double.parseDouble(seconds);
316                 secPresent = true;
317             } else {
318                 min = Double.parseDouble(minutes);
319             }
320 
321             boolean isNegative180 = negative && (deg == 180) &&
322                 (min == 0) && (sec == 0);
323 
324             // deg must be in [0, 179] except for the case of -180 degrees
325             if ((deg < 0.0) || (deg > 179 && !isNegative180)) {
326                 throw new IllegalArgumentException("coordinate=" + coordinate);
327             }
328 
329             // min must be in [0, 59] if seconds are present, otherwise [0.0, 60.0)
330             if (min < 0 || min >= 60 || (secPresent && (min > 59))) {
331                 throw new IllegalArgumentException("coordinate=" +
332                         coordinate);
333             }
334 
335             // sec must be in [0.0, 60.0)
336             if (sec < 0 || sec >= 60) {
337                 throw new IllegalArgumentException("coordinate=" +
338                         coordinate);
339             }
340 
341             val = deg*3600.0 + min*60.0 + sec;
342             val /= 3600.0;
343             return negative ? -val : val;
344         } catch (NumberFormatException nfe) {
345             throw new IllegalArgumentException("coordinate=" + coordinate);
346         }
347     }
348 
computeDistanceAndBearing(double lat1, double lon1, double lat2, double lon2, BearingDistanceCache results)349     private static void computeDistanceAndBearing(double lat1, double lon1,
350         double lat2, double lon2, BearingDistanceCache results) {
351         // Based on http://www.ngs.noaa.gov/PUBS_LIB/inverse.pdf
352         // using the "Inverse Formula" (section 4)
353 
354         int MAXITERS = 20;
355         // Convert lat/long to radians
356         lat1 *= Math.PI / 180.0;
357         lat2 *= Math.PI / 180.0;
358         lon1 *= Math.PI / 180.0;
359         lon2 *= Math.PI / 180.0;
360 
361         double a = 6378137.0; // WGS84 major axis
362         double b = 6356752.3142; // WGS84 semi-major axis
363         double f = (a - b) / a;
364         double aSqMinusBSqOverBSq = (a * a - b * b) / (b * b);
365 
366         double L = lon2 - lon1;
367         double A = 0.0;
368         double U1 = Math.atan((1.0 - f) * Math.tan(lat1));
369         double U2 = Math.atan((1.0 - f) * Math.tan(lat2));
370 
371         double cosU1 = Math.cos(U1);
372         double cosU2 = Math.cos(U2);
373         double sinU1 = Math.sin(U1);
374         double sinU2 = Math.sin(U2);
375         double cosU1cosU2 = cosU1 * cosU2;
376         double sinU1sinU2 = sinU1 * sinU2;
377 
378         double sigma = 0.0;
379         double deltaSigma = 0.0;
380         double cosSqAlpha = 0.0;
381         double cos2SM = 0.0;
382         double cosSigma = 0.0;
383         double sinSigma = 0.0;
384         double cosLambda = 0.0;
385         double sinLambda = 0.0;
386 
387         double lambda = L; // initial guess
388         for (int iter = 0; iter < MAXITERS; iter++) {
389             double lambdaOrig = lambda;
390             cosLambda = Math.cos(lambda);
391             sinLambda = Math.sin(lambda);
392             double t1 = cosU2 * sinLambda;
393             double t2 = cosU1 * sinU2 - sinU1 * cosU2 * cosLambda;
394             double sinSqSigma = t1 * t1 + t2 * t2; // (14)
395             sinSigma = Math.sqrt(sinSqSigma);
396             cosSigma = sinU1sinU2 + cosU1cosU2 * cosLambda; // (15)
397             sigma = Math.atan2(sinSigma, cosSigma); // (16)
398             double sinAlpha = (sinSigma == 0) ? 0.0 :
399                 cosU1cosU2 * sinLambda / sinSigma; // (17)
400             cosSqAlpha = 1.0 - sinAlpha * sinAlpha;
401             cos2SM = (cosSqAlpha == 0) ? 0.0 :
402                 cosSigma - 2.0 * sinU1sinU2 / cosSqAlpha; // (18)
403 
404             double uSquared = cosSqAlpha * aSqMinusBSqOverBSq; // defn
405             A = 1 + (uSquared / 16384.0) * // (3)
406                 (4096.0 + uSquared *
407                  (-768 + uSquared * (320.0 - 175.0 * uSquared)));
408             double B = (uSquared / 1024.0) * // (4)
409                 (256.0 + uSquared *
410                  (-128.0 + uSquared * (74.0 - 47.0 * uSquared)));
411             double C = (f / 16.0) *
412                 cosSqAlpha *
413                 (4.0 + f * (4.0 - 3.0 * cosSqAlpha)); // (10)
414             double cos2SMSq = cos2SM * cos2SM;
415             deltaSigma = B * sinSigma * // (6)
416                 (cos2SM + (B / 4.0) *
417                  (cosSigma * (-1.0 + 2.0 * cos2SMSq) -
418                   (B / 6.0) * cos2SM *
419                   (-3.0 + 4.0 * sinSigma * sinSigma) *
420                   (-3.0 + 4.0 * cos2SMSq)));
421 
422             lambda = L +
423                 (1.0 - C) * f * sinAlpha *
424                 (sigma + C * sinSigma *
425                  (cos2SM + C * cosSigma *
426                   (-1.0 + 2.0 * cos2SM * cos2SM))); // (11)
427 
428             double delta = (lambda - lambdaOrig) / lambda;
429             if (Math.abs(delta) < 1.0e-12) {
430                 break;
431             }
432         }
433 
434         float distance = (float) (b * A * (sigma - deltaSigma));
435         results.mDistance = distance;
436         float initialBearing = (float) Math.atan2(cosU2 * sinLambda,
437             cosU1 * sinU2 - sinU1 * cosU2 * cosLambda);
438         initialBearing *= 180.0 / Math.PI;
439         results.mInitialBearing = initialBearing;
440         float finalBearing = (float) Math.atan2(cosU1 * sinLambda,
441                 -sinU1 * cosU2 + cosU1 * sinU2 * cosLambda);
442         finalBearing *= 180.0 / Math.PI;
443         results.mFinalBearing = finalBearing;
444         results.mLat1 = lat1;
445         results.mLat2 = lat2;
446         results.mLon1 = lon1;
447         results.mLon2 = lon2;
448     }
449 
450     /**
451      * Computes the approximate distance in meters between two
452      * locations, and optionally the initial and final bearings of the
453      * shortest path between them.  Distance and bearing are defined using the
454      * WGS84 ellipsoid.
455      *
456      * <p> The computed distance is stored in results[0].  If results has length
457      * 2 or greater, the initial bearing is stored in results[1]. If results has
458      * length 3 or greater, the final bearing is stored in results[2].
459      *
460      * @param startLatitude the starting latitude
461      * @param startLongitude the starting longitude
462      * @param endLatitude the ending latitude
463      * @param endLongitude the ending longitude
464      * @param results an array of floats to hold the results
465      *
466      * @throws IllegalArgumentException if results is null or has length < 1
467      */
distanceBetween(double startLatitude, double startLongitude, double endLatitude, double endLongitude, float[] results)468     public static void distanceBetween(double startLatitude, double startLongitude,
469         double endLatitude, double endLongitude, float[] results) {
470         if (results == null || results.length < 1) {
471             throw new IllegalArgumentException("results is null or has length < 1");
472         }
473         BearingDistanceCache cache = sBearingDistanceCache.get();
474         computeDistanceAndBearing(startLatitude, startLongitude,
475                 endLatitude, endLongitude, cache);
476         results[0] = cache.mDistance;
477         if (results.length > 1) {
478             results[1] = cache.mInitialBearing;
479             if (results.length > 2) {
480                 results[2] = cache.mFinalBearing;
481             }
482         }
483     }
484 
485     /**
486      * Returns the approximate distance in meters between this
487      * location and the given location.  Distance is defined using
488      * the WGS84 ellipsoid.
489      *
490      * @param dest the destination location
491      * @return the approximate distance in meters
492      */
distanceTo(Location dest)493     public float distanceTo(Location dest) {
494         BearingDistanceCache cache = sBearingDistanceCache.get();
495         // See if we already have the result
496         if (mLatitude != cache.mLat1 || mLongitude != cache.mLon1 ||
497             dest.mLatitude != cache.mLat2 || dest.mLongitude != cache.mLon2) {
498             computeDistanceAndBearing(mLatitude, mLongitude,
499                 dest.mLatitude, dest.mLongitude, cache);
500         }
501         return cache.mDistance;
502     }
503 
504     /**
505      * Returns the approximate initial bearing in degrees East of true
506      * North when traveling along the shortest path between this
507      * location and the given location.  The shortest path is defined
508      * using the WGS84 ellipsoid.  Locations that are (nearly)
509      * antipodal may produce meaningless results.
510      *
511      * @param dest the destination location
512      * @return the initial bearing in degrees
513      */
bearingTo(Location dest)514     public float bearingTo(Location dest) {
515         BearingDistanceCache cache = sBearingDistanceCache.get();
516         // See if we already have the result
517         if (mLatitude != cache.mLat1 || mLongitude != cache.mLon1 ||
518                         dest.mLatitude != cache.mLat2 || dest.mLongitude != cache.mLon2) {
519             computeDistanceAndBearing(mLatitude, mLongitude,
520                 dest.mLatitude, dest.mLongitude, cache);
521         }
522         return cache.mInitialBearing;
523     }
524 
525     /**
526      * Returns the name of the provider that generated this fix.
527      *
528      * @return the provider, or null if it has not been set
529      */
getProvider()530     public String getProvider() {
531         return mProvider;
532     }
533 
534     /**
535      * Sets the name of the provider that generated this fix.
536      */
setProvider(String provider)537     public void setProvider(String provider) {
538         mProvider = provider;
539     }
540 
541     /**
542      * Return the UTC time of this fix, in milliseconds since January 1, 1970.
543      *
544      * <p>Note that the UTC time on a device is not monotonic: it
545      * can jump forwards or backwards unpredictably. So always use
546      * {@link #getElapsedRealtimeNanos} when calculating time deltas.
547      *
548      * <p>On the other hand, {@link #getTime} is useful for presenting
549      * a human readable time to the user, or for carefully comparing
550      * location fixes across reboot or across devices.
551      *
552      * <p>All locations generated by the {@link LocationManager}
553      * are guaranteed to have a valid UTC time, however remember that
554      * the system time may have changed since the location was generated.
555      *
556      * @return time of fix, in milliseconds since January 1, 1970.
557      */
getTime()558     public long getTime() {
559         return mTime;
560     }
561 
562     /**
563      * Set the UTC time of this fix, in milliseconds since January 1,
564      * 1970.
565      *
566      * @param time UTC time of this fix, in milliseconds since January 1, 1970
567      */
setTime(long time)568     public void setTime(long time) {
569         mTime = time;
570     }
571 
572     /**
573      * Return the time of this fix, in elapsed real-time since system boot.
574      *
575      * <p>This value can be reliably compared to
576      * {@link android.os.SystemClock#elapsedRealtimeNanos},
577      * to calculate the age of a fix and to compare Location fixes. This
578      * is reliable because elapsed real-time is guaranteed monotonic for
579      * each system boot and continues to increment even when the system
580      * is in deep sleep (unlike {@link #getTime}.
581      *
582      * <p>All locations generated by the {@link LocationManager}
583      * are guaranteed to have a valid elapsed real-time.
584      *
585      * @return elapsed real-time of fix, in nanoseconds since system boot.
586      */
getElapsedRealtimeNanos()587     public long getElapsedRealtimeNanos() {
588         return mElapsedRealtimeNanos;
589     }
590 
591     /**
592      * Set the time of this fix, in elapsed real-time since system boot.
593      *
594      * @param time elapsed real-time of fix, in nanoseconds since system boot.
595      */
setElapsedRealtimeNanos(long time)596     public void setElapsedRealtimeNanos(long time) {
597         mElapsedRealtimeNanos = time;
598     }
599 
600     /**
601      * Get estimate of the relative precision of the alignment of the
602      * ElapsedRealtimeNanos timestamp, with the reported measurements in
603      * nanoseconds (68% confidence).
604      *
605      * This means that we have 68% confidence that the true timestamp of the
606      * event is within ElapsedReatimeNanos +/- uncertainty.
607      *
608      * Example :
609      *   - getElapsedRealtimeNanos() returns 10000000
610      *   - getElapsedRealtimeUncertaintyNanos() returns 1000000 (equivalent to 1millisecond)
611      *   This means that the event most likely happened between 9000000 and 11000000.
612      *
613      * @return uncertainty of elapsed real-time of fix, in nanoseconds.
614      */
getElapsedRealtimeUncertaintyNanos()615     public double getElapsedRealtimeUncertaintyNanos() {
616         return mElapsedRealtimeUncertaintyNanos;
617     }
618 
619     /**
620      * Set estimate of the relative precision of the alignment of the
621      * ElapsedRealtimeNanos timestamp, with the reported measurements in
622      * nanoseconds (68% confidence).
623      *
624      * @param time uncertainty of the elapsed real-time of fix, in nanoseconds.
625      */
setElapsedRealtimeUncertaintyNanos(double time)626     public void setElapsedRealtimeUncertaintyNanos(double time) {
627         mElapsedRealtimeUncertaintyNanos = time;
628         mFieldsMask |= HAS_ELAPSED_REALTIME_UNCERTAINTY_MASK;
629     }
630 
631     /**
632      * True if this location has a elapsed realtime accuracy.
633      */
hasElapsedRealtimeUncertaintyNanos()634     public boolean hasElapsedRealtimeUncertaintyNanos() {
635         return (mFieldsMask & HAS_ELAPSED_REALTIME_UNCERTAINTY_MASK) != 0;
636     }
637 
638 
639     /**
640      * Get the latitude, in degrees.
641      *
642      * <p>All locations generated by the {@link LocationManager}
643      * will have a valid latitude.
644      */
getLatitude()645     public double getLatitude() {
646         return mLatitude;
647     }
648 
649     /**
650      * Set the latitude, in degrees.
651      */
setLatitude(double latitude)652     public void setLatitude(double latitude) {
653         mLatitude = latitude;
654     }
655 
656     /**
657      * Get the longitude, in degrees.
658      *
659      * <p>All locations generated by the {@link LocationManager}
660      * will have a valid longitude.
661      */
getLongitude()662     public double getLongitude() {
663         return mLongitude;
664     }
665 
666     /**
667      * Set the longitude, in degrees.
668      */
setLongitude(double longitude)669     public void setLongitude(double longitude) {
670         mLongitude = longitude;
671     }
672 
673     /**
674      * True if this location has an altitude.
675      */
hasAltitude()676     public boolean hasAltitude() {
677         return (mFieldsMask & HAS_ALTITUDE_MASK) != 0;
678     }
679 
680     /**
681      * Get the altitude if available, in meters above the WGS 84 reference
682      * ellipsoid.
683      *
684      * <p>If this location does not have an altitude then 0.0 is returned.
685      */
getAltitude()686     public double getAltitude() {
687         return mAltitude;
688     }
689 
690     /**
691      * Set the altitude, in meters above the WGS 84 reference ellipsoid.
692      *
693      * <p>Following this call {@link #hasAltitude} will return true.
694      */
setAltitude(double altitude)695     public void setAltitude(double altitude) {
696         mAltitude = altitude;
697         mFieldsMask |= HAS_ALTITUDE_MASK;
698     }
699 
700     /**
701      * Remove the altitude from this location.
702      *
703      * <p>Following this call {@link #hasAltitude} will return false,
704      * and {@link #getAltitude} will return 0.0.
705      *
706      * @deprecated use a new Location object for location updates.
707      */
708     @Deprecated
removeAltitude()709     public void removeAltitude() {
710         mAltitude = 0.0f;
711         mFieldsMask &= ~HAS_ALTITUDE_MASK;
712     }
713 
714     /**
715      * True if this location has a speed.
716      */
hasSpeed()717     public boolean hasSpeed() {
718         return (mFieldsMask & HAS_SPEED_MASK) != 0;
719     }
720 
721     /**
722      * Get the speed if it is available, in meters/second over ground.
723      *
724      * <p>If this location does not have a speed then 0.0 is returned.
725      */
getSpeed()726     public float getSpeed() {
727         return mSpeed;
728     }
729 
730     /**
731      * Set the speed, in meters/second over ground.
732      *
733      * <p>Following this call {@link #hasSpeed} will return true.
734      */
setSpeed(float speed)735     public void setSpeed(float speed) {
736         mSpeed = speed;
737         mFieldsMask |= HAS_SPEED_MASK;
738     }
739 
740     /**
741      * Remove the speed from this location.
742      *
743      * <p>Following this call {@link #hasSpeed} will return false,
744      * and {@link #getSpeed} will return 0.0.
745      *
746      * @deprecated use a new Location object for location updates.
747      */
748     @Deprecated
removeSpeed()749     public void removeSpeed() {
750         mSpeed = 0.0f;
751         mFieldsMask &= ~HAS_SPEED_MASK;
752     }
753 
754     /**
755      * True if this location has a bearing.
756      */
hasBearing()757     public boolean hasBearing() {
758         return (mFieldsMask & HAS_BEARING_MASK) != 0;
759     }
760 
761     /**
762      * Get the bearing, in degrees.
763      *
764      * <p>Bearing is the horizontal direction of travel of this device,
765      * and is not related to the device orientation. It is guaranteed to
766      * be in the range (0.0, 360.0] if the device has a bearing.
767      *
768      * <p>If this location does not have a bearing then 0.0 is returned.
769      */
getBearing()770     public float getBearing() {
771         return mBearing;
772     }
773 
774     /**
775      * Set the bearing, in degrees.
776      *
777      * <p>Bearing is the horizontal direction of travel of this device,
778      * and is not related to the device orientation.
779      *
780      * <p>The input will be wrapped into the range (0.0, 360.0].
781      */
setBearing(float bearing)782     public void setBearing(float bearing) {
783         while (bearing < 0.0f) {
784             bearing += 360.0f;
785         }
786         while (bearing >= 360.0f) {
787             bearing -= 360.0f;
788         }
789         mBearing = bearing;
790         mFieldsMask |= HAS_BEARING_MASK;
791     }
792 
793     /**
794      * Remove the bearing from this location.
795      *
796      * <p>Following this call {@link #hasBearing} will return false,
797      * and {@link #getBearing} will return 0.0.
798      *
799      * @deprecated use a new Location object for location updates.
800      */
801     @Deprecated
removeBearing()802     public void removeBearing() {
803         mBearing = 0.0f;
804         mFieldsMask &= ~HAS_BEARING_MASK;
805     }
806 
807     /**
808      * True if this location has a horizontal accuracy.
809      *
810      * <p>All locations generated by the {@link LocationManager} have an horizontal accuracy.
811      */
hasAccuracy()812     public boolean hasAccuracy() {
813         return (mFieldsMask & HAS_HORIZONTAL_ACCURACY_MASK) != 0;
814     }
815 
816     /**
817      * Get the estimated horizontal accuracy of this location, radial, in meters.
818      *
819      * <p>We define horizontal accuracy as the radius of 68% confidence. In other
820      * words, if you draw a circle centered at this location's
821      * latitude and longitude, and with a radius equal to the accuracy,
822      * then there is a 68% probability that the true location is inside
823      * the circle.
824      *
825      * <p>This accuracy estimation is only concerned with horizontal
826      * accuracy, and does not indicate the accuracy of bearing,
827      * velocity or altitude if those are included in this Location.
828      *
829      * <p>If this location does not have a horizontal accuracy, then 0.0 is returned.
830      * All locations generated by the {@link LocationManager} include horizontal accuracy.
831      */
getAccuracy()832     public float getAccuracy() {
833         return mHorizontalAccuracyMeters;
834     }
835 
836     /**
837      * Set the estimated horizontal accuracy of this location, meters.
838      *
839      * <p>See {@link #getAccuracy} for the definition of horizontal accuracy.
840      *
841      * <p>Following this call {@link #hasAccuracy} will return true.
842      */
setAccuracy(float horizontalAccuracy)843     public void setAccuracy(float horizontalAccuracy) {
844         mHorizontalAccuracyMeters = horizontalAccuracy;
845         mFieldsMask |= HAS_HORIZONTAL_ACCURACY_MASK;
846     }
847 
848     /**
849      * Remove the horizontal accuracy from this location.
850      *
851      * <p>Following this call {@link #hasAccuracy} will return false, and
852      * {@link #getAccuracy} will return 0.0.
853      *
854      * @deprecated use a new Location object for location updates.
855      */
856     @Deprecated
removeAccuracy()857     public void removeAccuracy() {
858         mHorizontalAccuracyMeters = 0.0f;
859         mFieldsMask &= ~HAS_HORIZONTAL_ACCURACY_MASK;
860     }
861 
862     /**
863      * True if this location has a vertical accuracy.
864      */
hasVerticalAccuracy()865     public boolean hasVerticalAccuracy() {
866         return (mFieldsMask & HAS_VERTICAL_ACCURACY_MASK) != 0;
867     }
868 
869     /**
870      * Get the estimated vertical accuracy of this location, in meters.
871      *
872      * <p>We define vertical accuracy at 68% confidence.  Specifically, as 1-side of the
873      * 2-sided range above and below the estimated altitude reported by {@link #getAltitude()},
874      * within which there is a 68% probability of finding the true altitude.
875      *
876      * <p>In the case where the underlying distribution is assumed Gaussian normal, this would be
877      * considered 1 standard deviation.
878      *
879      * <p>For example, if {@link #getAltitude()} returns 150, and
880      * {@link #getVerticalAccuracyMeters()} returns 20 then there is a 68% probability
881      * of the true altitude being between 130 and 170 meters.
882      *
883      * <p>If this location does not have a vertical accuracy, then 0.0 is returned.
884      */
getVerticalAccuracyMeters()885     public float getVerticalAccuracyMeters() {
886         return mVerticalAccuracyMeters;
887     }
888 
889     /**
890      * Set the estimated vertical accuracy of this location, meters.
891      *
892      * <p>See {@link #getVerticalAccuracyMeters} for the definition of vertical accuracy.
893      *
894      * <p>Following this call {@link #hasVerticalAccuracy} will return true.
895      */
setVerticalAccuracyMeters(float verticalAccuracyMeters)896     public void setVerticalAccuracyMeters(float verticalAccuracyMeters) {
897         mVerticalAccuracyMeters = verticalAccuracyMeters;
898         mFieldsMask |= HAS_VERTICAL_ACCURACY_MASK;
899     }
900 
901     /**
902      * Remove the vertical accuracy from this location.
903      *
904      * <p>Following this call {@link #hasVerticalAccuracy} will return false, and
905      * {@link #getVerticalAccuracyMeters} will return 0.0.
906      *
907      * @deprecated use a new Location object for location updates.
908      * @removed
909      */
910     @Deprecated
removeVerticalAccuracy()911     public void removeVerticalAccuracy() {
912         mVerticalAccuracyMeters = 0.0f;
913         mFieldsMask &= ~HAS_VERTICAL_ACCURACY_MASK;
914     }
915 
916     /**
917      * True if this location has a speed accuracy.
918      */
hasSpeedAccuracy()919     public boolean hasSpeedAccuracy() {
920         return (mFieldsMask & HAS_SPEED_ACCURACY_MASK) != 0;
921     }
922 
923     /**
924      * Get the estimated speed accuracy of this location, in meters per second.
925      *
926      * <p>We define speed accuracy at 68% confidence.  Specifically, as 1-side of the
927      * 2-sided range above and below the estimated speed reported by {@link #getSpeed()},
928      * within which there is a 68% probability of finding the true speed.
929      *
930      * <p>In the case where the underlying
931      * distribution is assumed Gaussian normal, this would be considered 1 standard deviation.
932      *
933      * <p>For example, if {@link #getSpeed()} returns 5, and
934      * {@link #getSpeedAccuracyMetersPerSecond()} returns 1, then there is a 68% probability of
935      * the true speed being between 4 and 6 meters per second.
936      *
937      * <p>Note that the speed and speed accuracy is often better than would be obtained simply from
938      * differencing sequential positions, such as when the Doppler measurements from GNSS satellites
939      * are used.
940      *
941      * <p>If this location does not have a speed accuracy, then 0.0 is returned.
942      */
getSpeedAccuracyMetersPerSecond()943     public float getSpeedAccuracyMetersPerSecond() {
944         return mSpeedAccuracyMetersPerSecond;
945     }
946 
947     /**
948      * Set the estimated speed accuracy of this location, meters per second.
949      *
950      * <p>See {@link #getSpeedAccuracyMetersPerSecond} for the definition of speed accuracy.
951      *
952      * <p>Following this call {@link #hasSpeedAccuracy} will return true.
953      */
setSpeedAccuracyMetersPerSecond(float speedAccuracyMeterPerSecond)954     public void setSpeedAccuracyMetersPerSecond(float speedAccuracyMeterPerSecond) {
955         mSpeedAccuracyMetersPerSecond = speedAccuracyMeterPerSecond;
956         mFieldsMask |= HAS_SPEED_ACCURACY_MASK;
957     }
958 
959     /**
960      * Remove the speed accuracy from this location.
961      *
962      * <p>Following this call {@link #hasSpeedAccuracy} will return false, and
963      * {@link #getSpeedAccuracyMetersPerSecond} will return 0.0.
964      *
965      * @deprecated use a new Location object for location updates.
966      * @removed
967      */
968     @Deprecated
removeSpeedAccuracy()969     public void removeSpeedAccuracy() {
970         mSpeedAccuracyMetersPerSecond = 0.0f;
971         mFieldsMask &= ~HAS_SPEED_ACCURACY_MASK;
972     }
973 
974     /**
975      * True if this location has a bearing accuracy.
976      */
hasBearingAccuracy()977     public boolean hasBearingAccuracy() {
978         return (mFieldsMask & HAS_BEARING_ACCURACY_MASK) != 0;
979     }
980 
981     /**
982      * Get the estimated bearing accuracy of this location, in degrees.
983      *
984      * <p>We define bearing accuracy at 68% confidence.  Specifically, as 1-side of the
985      * 2-sided range on each side of the estimated bearing reported by {@link #getBearing()},
986      * within which there is a 68% probability of finding the true bearing.
987      *
988      * <p>In the case where the underlying distribution is assumed Gaussian normal, this would be
989      * considered 1 standard deviation.
990      *
991      * <p>For example, if {@link #getBearing()} returns 60, and
992      * {@link #getBearingAccuracyDegrees()} returns 10, then there is a 68% probability of the
993      * true bearing being between 50 and 70 degrees.
994      *
995      * <p>If this location does not have a bearing accuracy, then 0.0 is returned.
996      */
getBearingAccuracyDegrees()997     public float getBearingAccuracyDegrees() {
998         return mBearingAccuracyDegrees;
999     }
1000 
1001     /**
1002      * Set the estimated bearing accuracy of this location, degrees.
1003      *
1004      * <p>See {@link #getBearingAccuracyDegrees} for the definition of bearing accuracy.
1005      *
1006      * <p>Following this call {@link #hasBearingAccuracy} will return true.
1007      */
setBearingAccuracyDegrees(float bearingAccuracyDegrees)1008     public void setBearingAccuracyDegrees(float bearingAccuracyDegrees) {
1009         mBearingAccuracyDegrees = bearingAccuracyDegrees;
1010         mFieldsMask |= HAS_BEARING_ACCURACY_MASK;
1011     }
1012 
1013     /**
1014      * Remove the bearing accuracy from this location.
1015      *
1016      * <p>Following this call {@link #hasBearingAccuracy} will return false, and
1017      * {@link #getBearingAccuracyDegrees} will return 0.0.
1018      *
1019      * @deprecated use a new Location object for location updates.
1020      * @removed
1021      */
1022     @Deprecated
removeBearingAccuracy()1023     public void removeBearingAccuracy() {
1024         mBearingAccuracyDegrees = 0.0f;
1025         mFieldsMask &= ~HAS_BEARING_ACCURACY_MASK;
1026     }
1027 
1028     /**
1029      * Return true if this Location object is complete.
1030      *
1031      * <p>A location object is currently considered complete if it has
1032      * a valid provider, accuracy, wall-clock time and elapsed real-time.
1033      *
1034      * <p>All locations supplied by the {@link LocationManager} to
1035      * applications must be complete.
1036      *
1037      * @see #makeComplete
1038      * @hide
1039      */
1040     @SystemApi
isComplete()1041     public boolean isComplete() {
1042         if (mProvider == null) return false;
1043         if (!hasAccuracy()) return false;
1044         if (mTime == 0) return false;
1045         if (mElapsedRealtimeNanos == 0) return false;
1046         return true;
1047     }
1048 
1049     /**
1050      * Helper to fill incomplete fields.
1051      *
1052      * <p>Used to assist in backwards compatibility with
1053      * Location objects received from applications.
1054      *
1055      * @see #isComplete
1056      * @hide
1057      */
1058     @TestApi
1059     @SystemApi
makeComplete()1060     public void makeComplete() {
1061         if (mProvider == null) mProvider = "?";
1062         if (!hasAccuracy()) {
1063             mFieldsMask |= HAS_HORIZONTAL_ACCURACY_MASK;
1064             mHorizontalAccuracyMeters = 100.0f;
1065         }
1066         if (mTime == 0) mTime = System.currentTimeMillis();
1067         if (mElapsedRealtimeNanos == 0) mElapsedRealtimeNanos = SystemClock.elapsedRealtimeNanos();
1068     }
1069 
1070     /**
1071      * Returns additional provider-specific information about the
1072      * location fix as a Bundle.  The keys and values are determined
1073      * by the provider.  If no additional information is available,
1074      * null is returned.
1075      *
1076      * <p> A number of common key/value pairs are listed
1077      * below. Providers that use any of the keys on this list must
1078      * provide the corresponding value as described below.
1079      *
1080      * <ul>
1081      * <li> satellites - the number of satellites used to derive the fix
1082      * </ul>
1083      */
getExtras()1084     public Bundle getExtras() {
1085         return mExtras;
1086     }
1087 
1088     /**
1089      * Sets the extra information associated with this fix to the
1090      * given Bundle.
1091      *
1092      * <p>Note this stores a copy of the given extras, so any changes to extras after calling this
1093      * method won't be reflected in the location bundle.
1094      */
setExtras(Bundle extras)1095     public void setExtras(Bundle extras) {
1096         mExtras = (extras == null) ? null : new Bundle(extras);
1097     }
1098 
1099     @Override
toString()1100     public String toString() {
1101         StringBuilder s = new StringBuilder();
1102         s.append("Location[");
1103         s.append(mProvider);
1104         s.append(String.format(" %.6f,%.6f", mLatitude, mLongitude));
1105         if (hasAccuracy()) s.append(String.format(" hAcc=%.0f", mHorizontalAccuracyMeters));
1106         else s.append(" hAcc=???");
1107         if (mTime == 0) {
1108             s.append(" t=?!?");
1109         }
1110         if (mElapsedRealtimeNanos == 0) {
1111             s.append(" et=?!?");
1112         } else {
1113             s.append(" et=");
1114             TimeUtils.formatDuration(mElapsedRealtimeNanos / 1000000L, s);
1115         }
1116         if (hasElapsedRealtimeUncertaintyNanos()) {
1117             s.append(" etAcc=");
1118             TimeUtils.formatDuration((long) (mElapsedRealtimeUncertaintyNanos / 1000000), s);
1119         }
1120         if (hasAltitude()) s.append(" alt=").append(mAltitude);
1121         if (hasSpeed()) s.append(" vel=").append(mSpeed);
1122         if (hasBearing()) s.append(" bear=").append(mBearing);
1123         if (hasVerticalAccuracy()) s.append(String.format(" vAcc=%.0f", mVerticalAccuracyMeters));
1124         else s.append(" vAcc=???");
1125         if (hasSpeedAccuracy()) s.append(String.format(" sAcc=%.0f", mSpeedAccuracyMetersPerSecond));
1126         else s.append(" sAcc=???");
1127         if (hasBearingAccuracy()) s.append(String.format(" bAcc=%.0f", mBearingAccuracyDegrees));
1128         else s.append(" bAcc=???");
1129         if (isFromMockProvider()) s.append(" mock");
1130 
1131         if (mExtras != null) {
1132             s.append(" {").append(mExtras).append('}');
1133         }
1134         s.append(']');
1135         return s.toString();
1136     }
1137 
dump(Printer pw, String prefix)1138     public void dump(Printer pw, String prefix) {
1139         pw.println(prefix + toString());
1140     }
1141 
1142     public static final @android.annotation.NonNull Parcelable.Creator<Location> CREATOR =
1143         new Parcelable.Creator<Location>() {
1144         @Override
1145         public Location createFromParcel(Parcel in) {
1146             String provider = in.readString();
1147             Location l = new Location(provider);
1148             l.mTime = in.readLong();
1149             l.mElapsedRealtimeNanos = in.readLong();
1150             l.mElapsedRealtimeUncertaintyNanos = in.readDouble();
1151             l.mFieldsMask = in.readInt();
1152             l.mLatitude = in.readDouble();
1153             l.mLongitude = in.readDouble();
1154             l.mAltitude = in.readDouble();
1155             l.mSpeed = in.readFloat();
1156             l.mBearing = in.readFloat();
1157             l.mHorizontalAccuracyMeters = in.readFloat();
1158             l.mVerticalAccuracyMeters = in.readFloat();
1159             l.mSpeedAccuracyMetersPerSecond = in.readFloat();
1160             l.mBearingAccuracyDegrees = in.readFloat();
1161             l.mExtras = Bundle.setDefusable(in.readBundle(), true);
1162             return l;
1163         }
1164 
1165         @Override
1166         public Location[] newArray(int size) {
1167             return new Location[size];
1168         }
1169     };
1170 
1171     @Override
describeContents()1172     public int describeContents() {
1173         return 0;
1174     }
1175 
1176     @Override
writeToParcel(Parcel parcel, int flags)1177     public void writeToParcel(Parcel parcel, int flags) {
1178         parcel.writeString(mProvider);
1179         parcel.writeLong(mTime);
1180         parcel.writeLong(mElapsedRealtimeNanos);
1181         parcel.writeDouble(mElapsedRealtimeUncertaintyNanos);
1182         parcel.writeInt(mFieldsMask);
1183         parcel.writeDouble(mLatitude);
1184         parcel.writeDouble(mLongitude);
1185         parcel.writeDouble(mAltitude);
1186         parcel.writeFloat(mSpeed);
1187         parcel.writeFloat(mBearing);
1188         parcel.writeFloat(mHorizontalAccuracyMeters);
1189         parcel.writeFloat(mVerticalAccuracyMeters);
1190         parcel.writeFloat(mSpeedAccuracyMetersPerSecond);
1191         parcel.writeFloat(mBearingAccuracyDegrees);
1192         parcel.writeBundle(mExtras);
1193     }
1194 
1195     /**
1196      * Returns one of the optional extra {@link Location}s that can be attached
1197      * to this Location.
1198      *
1199      * @param key the key associated with the desired extra Location
1200      * @return the extra Location, or null if unavailable
1201      * @hide
1202      */
getExtraLocation(String key)1203     public Location getExtraLocation(String key) {
1204         if (mExtras != null) {
1205             Parcelable value = mExtras.getParcelable(key);
1206             if (value instanceof Location) {
1207                 return (Location) value;
1208             }
1209         }
1210         return null;
1211     }
1212 
1213     /**
1214      * Attaches an extra {@link Location} to this Location.
1215      *
1216      * @param key the key associated with the Location extra
1217      * @param value the Location to attach
1218      * @hide
1219      */
1220     @UnsupportedAppUsage
setExtraLocation(String key, Location value)1221     public void setExtraLocation(String key, Location value) {
1222         if (mExtras == null) {
1223             mExtras = new Bundle();
1224         }
1225         mExtras.putParcelable(key, value);
1226     }
1227 
1228     /**
1229      * Returns true if the Location came from a mock provider.
1230      *
1231      * @return true if this Location came from a mock provider, false otherwise
1232      */
isFromMockProvider()1233     public boolean isFromMockProvider() {
1234         return (mFieldsMask & HAS_MOCK_PROVIDER_MASK) != 0;
1235     }
1236 
1237     /**
1238      * Flag this Location as having come from a mock provider or not.
1239      *
1240      * @param isFromMockProvider true if this Location came from a mock provider, false otherwise
1241      * @hide
1242      */
1243     @SystemApi
setIsFromMockProvider(boolean isFromMockProvider)1244     public void setIsFromMockProvider(boolean isFromMockProvider) {
1245         if (isFromMockProvider) {
1246             mFieldsMask |= HAS_MOCK_PROVIDER_MASK;
1247         } else {
1248             mFieldsMask &= ~HAS_MOCK_PROVIDER_MASK;
1249         }
1250     }
1251 
1252     /**
1253      * Caches data used to compute distance and bearing (so successive calls to {@link #distanceTo}
1254      * and {@link #bearingTo} don't duplicate work.
1255      */
1256     private static class BearingDistanceCache {
1257         private double mLat1 = 0.0;
1258         private double mLon1 = 0.0;
1259         private double mLat2 = 0.0;
1260         private double mLon2 = 0.0;
1261         private float mDistance = 0.0f;
1262         private float mInitialBearing = 0.0f;
1263         private float mFinalBearing = 0.0f;
1264     }
1265 }
1266