Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 923b2602 authored by David Christie's avatar David Christie
Browse files

Make Location objects take less memory. 

-Use bitmask for has*** methods.
-Use ThreadLocal for caching intermediate computations
 rather than preallocating memory in every Location

Change-Id: If2fa17bfd59511ec0b809f4b7d7cd8028360c340
parent ab253faa

location/java/android/location/Location.java

+115 −100
Original line number Diff line number Diff line
@@ -78,32 +78,51 @@ public class Location implements Parcelable { 
     */

    public static final String EXTRA_NO_GPS_LOCATION = "noGPSLocation";



    /**

     * Bit mask for mFieldsMask indicating the presence of mAltitude.

     */

    private static final byte HAS_ALTITUDE_MASK = 1;

    /**

     * Bit mask for mFieldsMask indicating the presence of mSpeed.

     */

    private static final byte HAS_SPEED_MASK = 2;

    /**

     * Bit mask for mFieldsMask indicating the presence of mBearing.

     */

    private static final byte HAS_BEARING_MASK = 4;

    /**

     * Bit mask for mFieldsMask indicating the presence of mAccuracy.

     */

    private static final byte HAS_ACCURACY_MASK = 8;

    /**

     * Bit mask for mFieldsMask indicating location is from a mock provider.

     */

    private static final byte HAS_MOCK_PROVIDER_MASK = 16;



    // Cached data to make bearing/distance computations more efficient for the case

    // where distanceTo and bearingTo are called in sequence.  Assume this typically happens

    // on the same thread for caching purposes.

    private static ThreadLocal<BearingDistanceCache> sBearingDistanceCache

            = new ThreadLocal<BearingDistanceCache>() {

        @Override

        protected BearingDistanceCache initialValue() {

            return new BearingDistanceCache();

        }

    };



    private String mProvider;

    private long mTime = 0;

    private long mElapsedRealtimeNanos = 0;

    private double mLatitude = 0.0;

    private double mLongitude = 0.0;

    private boolean mHasAltitude = false;

    private double mAltitude = 0.0f;

    private boolean mHasSpeed = false;

    private float mSpeed = 0.0f;

    private boolean mHasBearing = false;

    private float mBearing = 0.0f;

    private boolean mHasAccuracy = false;

    private float mAccuracy = 0.0f;

    private Bundle mExtras = null;

    private boolean mIsFromMockProvider = false;



    // Cache the inputs and outputs of computeDistanceAndBearing

    // so calls to distanceTo() and bearingTo() can share work

    private double mLat1 = 0.0;

    private double mLon1 = 0.0;

    private double mLat2 = 0.0;

    private double mLon2 = 0.0;

    private float mDistance = 0.0f;

    private float mInitialBearing = 0.0f;

    // Scratchpad

    private final float[] mResults = new float[2];

    // A bitmask of fields present in this object (see HAS_* constants defined above).

    private byte mFieldsMask = 0;



    /**

     * Construct a new Location with a named provider.
@@ -131,18 +150,14 @@ public class Location implements Parcelable { 
        mProvider = l.mProvider;

        mTime = l.mTime;

        mElapsedRealtimeNanos = l.mElapsedRealtimeNanos;

        mFieldsMask = l.mFieldsMask;

        mLatitude = l.mLatitude;

        mLongitude = l.mLongitude;

        mHasAltitude = l.mHasAltitude;

        mAltitude = l.mAltitude;

        mHasSpeed = l.mHasSpeed;

        mSpeed = l.mSpeed;

        mHasBearing = l.mHasBearing;

        mBearing = l.mBearing;

        mHasAccuracy = l.mHasAccuracy;

        mAccuracy = l.mAccuracy;

        mExtras = (l.mExtras == null) ? null : new Bundle(l.mExtras);

        mIsFromMockProvider = l.mIsFromMockProvider;

    }



    /**
@@ -152,18 +167,14 @@ public class Location implements Parcelable { 
        mProvider = null;

        mTime = 0;

        mElapsedRealtimeNanos = 0;

        mFieldsMask = 0;

        mLatitude = 0;

        mLongitude = 0;

        mHasAltitude = false;

        mAltitude = 0;

        mHasSpeed = false;

        mSpeed = 0;

        mHasBearing = false;

        mBearing = 0;

        mHasAccuracy = false;

        mAccuracy = 0;

        mExtras = null;

        mIsFromMockProvider = false;

    }



    /**
@@ -297,7 +308,7 @@ public class Location implements Parcelable { 
    }



    private static void computeDistanceAndBearing(double lat1, double lon1,

        double lat2, double lon2, float[] results) {

        double lat2, double lon2, BearingDistanceCache results) {

        // Based on http://www.ngs.noaa.gov/PUBS_LIB/inverse.pdf

        // using the "Inverse Formula" (section 4)
@@ -382,19 +393,19 @@ public class Location implements Parcelable { 
        }



        float distance = (float) (b * A * (sigma - deltaSigma));

        results[0] = distance;

        if (results.length > 1) {

        results.mDistance = distance;

        float initialBearing = (float) Math.atan2(cosU2 * sinLambda,

            cosU1 * sinU2 - sinU1 * cosU2 * cosLambda);

        initialBearing *= 180.0 / Math.PI;

            results[1] = initialBearing;

            if (results.length > 2) {

        results.mInitialBearing = initialBearing;

        float finalBearing = (float) Math.atan2(cosU1 * sinLambda,

                -sinU1 * cosU2 + cosU1 * sinU2 * cosLambda);

        finalBearing *= 180.0 / Math.PI;

                results[2] = finalBearing;

            }

        }

        results.mFinalBearing = finalBearing;

        results.mLat1 = lat1;

        results.mLat2 = lat2;

        results.mLon1 = lon1;

        results.mLon2 = lon2;

    }



    /**
@@ -420,8 +431,16 @@ public class Location implements Parcelable { 
        if (results == null || results.length < 1) {

            throw new IllegalArgumentException("results is null or has length < 1");

        }

        BearingDistanceCache cache = sBearingDistanceCache.get();

        computeDistanceAndBearing(startLatitude, startLongitude,

            endLatitude, endLongitude, results);

                endLatitude, endLongitude, cache);

        results[0] = cache.mDistance;

        if (results.length > 1) {

            results[1] = cache.mInitialBearing;

            if (results.length > 2) {

                results[2] = cache.mFinalBearing;

            }

        }

    }



    /**
@@ -433,21 +452,14 @@ public class Location implements Parcelable { 
     * @return the approximate distance in meters

     */

    public float distanceTo(Location dest) {

        BearingDistanceCache cache = sBearingDistanceCache.get();

        // See if we already have the result

        synchronized (mResults) {

            if (mLatitude != mLat1 || mLongitude != mLon1 ||

                dest.mLatitude != mLat2 || dest.mLongitude != mLon2) {

        if (mLatitude != cache.mLat1 || mLongitude != cache.mLon1 ||

            dest.mLatitude != cache.mLat2 || dest.mLongitude != cache.mLon2) {

            computeDistanceAndBearing(mLatitude, mLongitude,

                    dest.mLatitude, dest.mLongitude, mResults);

                mLat1 = mLatitude;

                mLon1 = mLongitude;

                mLat2 = dest.mLatitude;

                mLon2 = dest.mLongitude;

                mDistance = mResults[0];

                mInitialBearing = mResults[1];

            }

            return mDistance;

                dest.mLatitude, dest.mLongitude, cache);

        }

        return cache.mDistance;

    }



    /**
@@ -461,21 +473,14 @@ public class Location implements Parcelable { 
     * @return the initial bearing in degrees

     */

    public float bearingTo(Location dest) {

        synchronized (mResults) {

        BearingDistanceCache cache = sBearingDistanceCache.get();

        // See if we already have the result

            if (mLatitude != mLat1 || mLongitude != mLon1 ||

                            dest.mLatitude != mLat2 || dest.mLongitude != mLon2) {

        if (mLatitude != cache.mLat1 || mLongitude != cache.mLon1 ||

                        dest.mLatitude != cache.mLat2 || dest.mLongitude != cache.mLon2) {

            computeDistanceAndBearing(mLatitude, mLongitude,

                    dest.mLatitude, dest.mLongitude, mResults);

                mLat1 = mLatitude;

                mLon1 = mLongitude;

                mLat2 = dest.mLatitude;

                mLon2 = dest.mLongitude;

                mDistance = mResults[0];

                mInitialBearing = mResults[1];

            }

            return mInitialBearing;

                dest.mLatitude, dest.mLongitude, cache);

        }

        return cache.mInitialBearing;

    }



    /**
@@ -591,7 +596,7 @@ public class Location implements Parcelable { 
     * True if this location has an altitude.

     */

    public boolean hasAltitude() {

        return mHasAltitude;

        return (mFieldsMask & HAS_ALTITUDE_MASK) != 0;

    }



    /**
@@ -611,7 +616,7 @@ public class Location implements Parcelable { 
     */

    public void setAltitude(double altitude) {

        mAltitude = altitude;

        mHasAltitude = true;

        mFieldsMask |= HAS_ALTITUDE_MASK;

    }



    /**
@@ -622,14 +627,14 @@ public class Location implements Parcelable { 
     */

    public void removeAltitude() {

        mAltitude = 0.0f;

        mHasAltitude = false;

        mFieldsMask &= ~HAS_ALTITUDE_MASK;

    }



    /**

     * True if this location has a speed.

     */

    public boolean hasSpeed() {

        return mHasSpeed;

        return (mFieldsMask & HAS_SPEED_MASK) != 0;

    }



    /**
@@ -648,7 +653,7 @@ public class Location implements Parcelable { 
     */

    public void setSpeed(float speed) {

        mSpeed = speed;

        mHasSpeed = true;

        mFieldsMask |= HAS_SPEED_MASK;

    }



    /**
@@ -659,14 +664,14 @@ public class Location implements Parcelable { 
     */

    public void removeSpeed() {

        mSpeed = 0.0f;

        mHasSpeed = false;

        mFieldsMask &= ~HAS_SPEED_MASK;

    }



    /**

     * True if this location has a bearing.

     */

    public boolean hasBearing() {

        return mHasBearing;

        return (mFieldsMask & HAS_BEARING_MASK) != 0;

    }



    /**
@@ -698,7 +703,7 @@ public class Location implements Parcelable { 
            bearing -= 360.0f;

        }

        mBearing = bearing;

        mHasBearing = true;

        mFieldsMask |= HAS_BEARING_MASK;

    }



    /**
@@ -709,7 +714,7 @@ public class Location implements Parcelable { 
     */

    public void removeBearing() {

        mBearing = 0.0f;

        mHasBearing = false;

        mFieldsMask &= ~HAS_BEARING_MASK;

    }



    /**
@@ -719,7 +724,7 @@ public class Location implements Parcelable { 
     * accuracy.

     */

    public boolean hasAccuracy() {

        return mHasAccuracy;

        return (mFieldsMask & HAS_ACCURACY_MASK) != 0;

    }



    /**
@@ -757,7 +762,7 @@ public class Location implements Parcelable { 
     */

    public void setAccuracy(float accuracy) {

        mAccuracy = accuracy;

        mHasAccuracy = true;

        mFieldsMask |= HAS_ACCURACY_MASK;

    }



    /**
@@ -768,7 +773,7 @@ public class Location implements Parcelable { 
     */

    public void removeAccuracy() {

        mAccuracy = 0.0f;

        mHasAccuracy = false;

        mFieldsMask &= ~HAS_ACCURACY_MASK;

    }



    /**
@@ -786,7 +791,7 @@ public class Location implements Parcelable { 
    @SystemApi

    public boolean isComplete() {

        if (mProvider == null) return false;

        if (!mHasAccuracy) return false;

        if (!hasAccuracy()) return false;

        if (mTime == 0) return false;

        if (mElapsedRealtimeNanos == 0) return false;

        return true;
@@ -804,8 +809,8 @@ public class Location implements Parcelable { 
    @SystemApi

    public void makeComplete() {

        if (mProvider == null) mProvider = "?";

        if (!mHasAccuracy) {

            mHasAccuracy = true;

        if (!hasAccuracy()) {

            mFieldsMask |= HAS_ACCURACY_MASK;

            mAccuracy = 100.0f;

        }

        if (mTime == 0) mTime = System.currentTimeMillis();
@@ -844,7 +849,7 @@ public class Location implements Parcelable { 
        s.append("Location[");

        s.append(mProvider);

        s.append(String.format(" %.6f,%.6f", mLatitude, mLongitude));

        if (mHasAccuracy) s.append(String.format(" acc=%.0f", mAccuracy));

        if (hasAccuracy()) s.append(String.format(" acc=%.0f", mAccuracy));

        else s.append(" acc=???");

        if (mTime == 0) {

            s.append(" t=?!?");
@@ -855,10 +860,10 @@ public class Location implements Parcelable { 
            s.append(" et=");

            TimeUtils.formatDuration(mElapsedRealtimeNanos / 1000000L, s);

        }

        if (mHasAltitude) s.append(" alt=").append(mAltitude);

        if (mHasSpeed) s.append(" vel=").append(mSpeed);

        if (mHasBearing) s.append(" bear=").append(mBearing);

        if (mIsFromMockProvider) s.append(" mock");

        if (hasAltitude()) s.append(" alt=").append(mAltitude);

        if (hasSpeed()) s.append(" vel=").append(mSpeed);

        if (hasBearing()) s.append(" bear=").append(mBearing);

        if (isFromMockProvider()) s.append(" mock");



        if (mExtras != null) {

            s.append(" {").append(mExtras).append('}');
@@ -879,18 +884,14 @@ public class Location implements Parcelable { 
            Location l = new Location(provider);

            l.mTime = in.readLong();

            l.mElapsedRealtimeNanos = in.readLong();

            l.mFieldsMask = in.readByte();

            l.mLatitude = in.readDouble();

            l.mLongitude = in.readDouble();

            l.mHasAltitude = in.readInt() != 0;

            l.mAltitude = in.readDouble();

            l.mHasSpeed = in.readInt() != 0;

            l.mSpeed = in.readFloat();

            l.mHasBearing = in.readInt() != 0;

            l.mBearing = in.readFloat();

            l.mHasAccuracy = in.readInt() != 0;

            l.mAccuracy = in.readFloat();

            l.mExtras = in.readBundle();

            l.mIsFromMockProvider = in.readInt() != 0;

            return l;

        }
@@ -910,18 +911,14 @@ public class Location implements Parcelable { 
        parcel.writeString(mProvider);

        parcel.writeLong(mTime);

        parcel.writeLong(mElapsedRealtimeNanos);

        parcel.writeByte(mFieldsMask);

        parcel.writeDouble(mLatitude);

        parcel.writeDouble(mLongitude);

        parcel.writeInt(mHasAltitude ? 1 : 0);

        parcel.writeDouble(mAltitude);

        parcel.writeInt(mHasSpeed ? 1 : 0);

        parcel.writeFloat(mSpeed);

        parcel.writeInt(mHasBearing ? 1 : 0);

        parcel.writeFloat(mBearing);

        parcel.writeInt(mHasAccuracy ? 1 : 0);

        parcel.writeFloat(mAccuracy);

        parcel.writeBundle(mExtras);

        parcel.writeInt(mIsFromMockProvider? 1 : 0);

    }



    /**
@@ -946,7 +943,7 @@ public class Location implements Parcelable { 
     * Attaches an extra {@link Location} to this Location.

     *

     * @param key the key associated with the Location extra

     * @param location the Location to attach

     * @param value the Location to attach

     * @hide

     */

    public void setExtraLocation(String key, Location value) {
@@ -962,7 +959,7 @@ public class Location implements Parcelable { 
     * @return true if this Location came from a mock provider, false otherwise

     */

    public boolean isFromMockProvider() {

        return mIsFromMockProvider;

        return (mFieldsMask & HAS_MOCK_PROVIDER_MASK) != 0;

    }



    /**
@@ -973,6 +970,24 @@ public class Location implements Parcelable { 
     */

    @SystemApi

    public void setIsFromMockProvider(boolean isFromMockProvider) {

        mIsFromMockProvider = isFromMockProvider;

        if (isFromMockProvider) {

            mFieldsMask |= HAS_MOCK_PROVIDER_MASK;

        } else {

            mFieldsMask &= ~HAS_MOCK_PROVIDER_MASK;

        }

    }



    /**

     * Caches data used to compute distance and bearing (so successive calls to {@link #distanceTo}

     * and {@link #bearingTo} don't duplicate work.

     */

    private static class BearingDistanceCache {

        private double mLat1 = 0.0;

        private double mLon1 = 0.0;

        private double mLat2 = 0.0;

        private double mLon2 = 0.0;

        private float mDistance = 0.0f;

        private float mInitialBearing = 0.0f;

        private float mFinalBearing = 0.0f;

    }

}

location/tests/locationtests/src/android/location/LocationTest.java

+35 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 


package android.location;



import android.os.Parcel;

import android.test.suitebuilder.annotation.SmallTest;



import junit.framework.TestCase;
@@ -225,6 +226,40 @@ public class LocationTest extends TestCase { 
        assertEquals(message, loc.getBearing(), 0, 0);

    }



    public void testParcel() {

        final double expectedLat = 33;

        final double expectedLon = -122;

        final float expectedAccuracy = 15;

        final float expectedSpeed = 5;

        Location loc = new Location("test");

        loc.setLatitude(expectedLat);

        loc.setLongitude(expectedLon);

        loc.setAccuracy(expectedAccuracy);

        loc.setSpeed(expectedSpeed);



        // Serialize location object into bytes via parcelable capability

        Parcel parcel = Parcel.obtain();

        loc.writeToParcel(parcel, 0);

        byte[] rawBytes = parcel.marshall();

        parcel.recycle();



        // Turn the bytes back into a location object

        parcel = Parcel.obtain();

        parcel.unmarshall(rawBytes, 0, rawBytes.length);

        parcel.setDataPosition(0);

        Location deserialized = Location.CREATOR.createFromParcel(parcel);

        parcel.recycle();



        assertEquals(expectedLat, deserialized.getLatitude());

        assertEquals(expectedLon, deserialized.getLongitude());

        assertEquals(expectedAccuracy, deserialized.getAccuracy());

        assertTrue(deserialized.hasAccuracy());

        assertEquals(expectedSpeed, deserialized.getSpeed());

        assertTrue(deserialized.hasSpeed());

        assertFalse(deserialized.hasBearing());

        assertFalse(deserialized.hasAltitude());

        assertFalse(deserialized.isFromMockProvider());

    }

}