location/java/android/location/GnssStatus.java - LeafOS-Project/android_frameworks_base - Gitiles

 /*
  * Copyright (C) 2016 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package android.location;

 import android.annotation.FloatRange;
 import android.annotation.IntDef;
 import android.annotation.IntRange;
 import android.annotation.NonNull;
 import android.os.Parcel;
 import android.os.Parcelable;

 import com.android.internal.util.Preconditions;

 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Objects;

 /**
  * This class represents the current state of the GNSS engine and is used in conjunction with
  * {@link GnssStatus.Callback}.
  *
  * @see LocationManager#registerGnssStatusCallback
  * @see GnssStatus.Callback
  */
 public final class GnssStatus implements Parcelable {

     // These must match the definitions in GNSS HAL.
     //
     // Note: these constants are also duplicated in GnssStatusCompat.java in the androidx support
     // library. if adding a constellation, please update that file as well.

     /** Unknown constellation type. */
     public static final int CONSTELLATION_UNKNOWN = 0;
     /** Constellation type constant for GPS. */
     public static final int CONSTELLATION_GPS = 1;
     /** Constellation type constant for SBAS. */
     public static final int CONSTELLATION_SBAS = 2;
     /** Constellation type constant for Glonass. */
     public static final int CONSTELLATION_GLONASS = 3;
     /** Constellation type constant for QZSS. */
     public static final int CONSTELLATION_QZSS = 4;
     /** Constellation type constant for Beidou. */
     public static final int CONSTELLATION_BEIDOU = 5;
     /** Constellation type constant for Galileo. */
     public static final int CONSTELLATION_GALILEO = 6;
     /** Constellation type constant for IRNSS. */
     public static final int CONSTELLATION_IRNSS = 7;
     /** @hide */
     public static final int CONSTELLATION_COUNT = 8;

     private static final int SVID_FLAGS_NONE = 0;
     private static final int SVID_FLAGS_HAS_EPHEMERIS_DATA = (1 << 0);
     private static final int SVID_FLAGS_HAS_ALMANAC_DATA = (1 << 1);
     private static final int SVID_FLAGS_USED_IN_FIX = (1 << 2);
     private static final int SVID_FLAGS_HAS_CARRIER_FREQUENCY = (1 << 3);
     private static final int SVID_FLAGS_HAS_BASEBAND_CN0 = (1 << 4);

     private static final int SVID_SHIFT_WIDTH = 12;
     private static final int CONSTELLATION_TYPE_SHIFT_WIDTH = 8;
     private static final int CONSTELLATION_TYPE_MASK = 0xf;

     /**
      * Used for receiving notifications when GNSS events happen.
      *
      * @see LocationManager#registerGnssStatusCallback
      */
     public static abstract class Callback {
         /**
          * Called when GNSS system has started.
          */
         public void onStarted() {
         }

         /**
          * Called when GNSS system has stopped.
          */
         public void onStopped() {
         }

         /**
          * Called when the GNSS system has received its first fix since starting.
          *
          * @param ttffMillis the time from start to first fix in milliseconds.
          */
         public void onFirstFix(int ttffMillis) {
         }

         /**
          * Called periodically to report GNSS satellite status.
          *
          * @param status the current status of all satellites.
          */
         public void onSatelliteStatusChanged(@NonNull GnssStatus status) {
         }
     }

     /**
      * Constellation type.
      *
      * @hide
      */
     @Retention(RetentionPolicy.SOURCE)
     @IntDef({CONSTELLATION_UNKNOWN, CONSTELLATION_GPS, CONSTELLATION_SBAS, CONSTELLATION_GLONASS,
             CONSTELLATION_QZSS, CONSTELLATION_BEIDOU, CONSTELLATION_GALILEO, CONSTELLATION_IRNSS})
     public @interface ConstellationType {
     }

     /**
      * Create a GnssStatus that wraps the given arguments without any additional overhead. Callers
      * are responsible for guaranteeing that the arguments are never modified after calling this
      * method.
      *
      * @hide
      */
     @NonNull
     public static GnssStatus wrap(int svCount, int[] svidWithFlags, float[] cn0DbHzs,
             float[] elevations, float[] azimuths, float[] carrierFrequencies,
             float[] basebandCn0DbHzs) {
         Preconditions.checkState(svCount >= 0);
         Preconditions.checkState(svidWithFlags.length >= svCount);
         Preconditions.checkState(elevations.length >= svCount);
         Preconditions.checkState(azimuths.length >= svCount);
         Preconditions.checkState(carrierFrequencies.length >= svCount);
         Preconditions.checkState(basebandCn0DbHzs.length >= svCount);

         return new GnssStatus(svCount, svidWithFlags, cn0DbHzs, elevations, azimuths,
                 carrierFrequencies, basebandCn0DbHzs);
     }

     private final int mSvCount;
     private final int[] mSvidWithFlags;
     private final float[] mCn0DbHzs;
     private final float[] mElevations;
     private final float[] mAzimuths;
     private final float[] mCarrierFrequencies;
     private final float[] mBasebandCn0DbHzs;

     private GnssStatus(int svCount, int[] svidWithFlags, float[] cn0DbHzs, float[] elevations,
             float[] azimuths, float[] carrierFrequencies, float[] basebandCn0DbHzs) {
         mSvCount = svCount;
         mSvidWithFlags = svidWithFlags;
         mCn0DbHzs = cn0DbHzs;
         mElevations = elevations;
         mAzimuths = azimuths;
         mCarrierFrequencies = carrierFrequencies;
         mBasebandCn0DbHzs = basebandCn0DbHzs;
     }

     /**
      * Gets the total number of satellites in satellite list.
      */
     @IntRange(from = 0)
     public int getSatelliteCount() {
         return mSvCount;
     }

     /**
      * Retrieves the constellation type of the satellite at the specified index.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     @ConstellationType
     public int getConstellationType(@IntRange(from = 0) int satelliteIndex) {
         return ((mSvidWithFlags[satelliteIndex] >> CONSTELLATION_TYPE_SHIFT_WIDTH)
                 & CONSTELLATION_TYPE_MASK);
     }

     /**
      * Gets the identification number for the satellite at the specific index.
      *
      * <p>This svid is pseudo-random number for most constellations. It is FCN &amp; OSN number for
      * Glonass.
      *
      * <p>The distinction is made by looking at constellation field
      * {@link #getConstellationType(int)} Expected values are in the range of:
      *
      * <ul>
      * <li>GPS: 1-32</li>
      * <li>SBAS: 120-151, 183-192</li>
      * <li>GLONASS: One of: OSN, or FCN+100
      * <ul>
      * <li>1-24 as the orbital slot number (OSN) (preferred, if known)</li>
      * <li>93-106 as the frequency channel number (FCN) (-7 to +6) plus 100.
      * i.e. encode FCN of -7 as 93, 0 as 100, and +6 as 106</li>
      * </ul></li>
      * <li>QZSS: 193-200</li>
      * <li>Galileo: 1-36</li>
      * <li>Beidou: 1-37</li>
      * <li>IRNSS: 1-14</li>
      * </ul>
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     @IntRange(from = 1, to = 200)
     public int getSvid(@IntRange(from = 0) int satelliteIndex) {
         return mSvidWithFlags[satelliteIndex] >> SVID_SHIFT_WIDTH;
     }

     /**
      * Retrieves the carrier-to-noise density at the antenna of the satellite at the specified index
      * in dB-Hz.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     @FloatRange(from = 0, to = 63)
     public float getCn0DbHz(@IntRange(from = 0) int satelliteIndex) {
         return mCn0DbHzs[satelliteIndex];
     }

     /**
      * Retrieves the elevation of the satellite at the specified index.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     @FloatRange(from = -90, to = 90)
     public float getElevationDegrees(@IntRange(from = 0) int satelliteIndex) {
         return mElevations[satelliteIndex];
     }

     /**
      * Retrieves the azimuth the satellite at the specified index.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     @FloatRange(from = 0, to = 360)
     public float getAzimuthDegrees(@IntRange(from = 0) int satelliteIndex) {
         return mAzimuths[satelliteIndex];
     }

     /**
      * Reports whether the satellite at the specified index has ephemeris data.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     public boolean hasEphemerisData(@IntRange(from = 0) int satelliteIndex) {
         return (mSvidWithFlags[satelliteIndex] & SVID_FLAGS_HAS_EPHEMERIS_DATA) != 0;
     }

     /**
      * Reports whether the satellite at the specified index has almanac data.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     public boolean hasAlmanacData(@IntRange(from = 0) int satelliteIndex) {
         return (mSvidWithFlags[satelliteIndex] & SVID_FLAGS_HAS_ALMANAC_DATA) != 0;
     }

     /**
      * Reports whether the satellite at the specified index was used in the calculation of the most
      * recent position fix.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     public boolean usedInFix(@IntRange(from = 0) int satelliteIndex) {
         return (mSvidWithFlags[satelliteIndex] & SVID_FLAGS_USED_IN_FIX) != 0;
     }

     /**
      * Reports whether a valid {@link #getCarrierFrequencyHz(int satelliteIndex)} is available.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     public boolean hasCarrierFrequencyHz(@IntRange(from = 0) int satelliteIndex) {
         return (mSvidWithFlags[satelliteIndex] & SVID_FLAGS_HAS_CARRIER_FREQUENCY) != 0;
     }

     /**
      * Gets the carrier frequency of the signal tracked.
      *
      * <p>For example it can be the GPS central frequency for L1 = 1575.45 MHz, or L2 = 1227.60
      * MHz, L5 = 1176.45 MHz, varying GLO channels, etc. If the field is not set, it is the primary
      * common use central frequency, e.g. L1 = 1575.45 MHz for GPS.
      *
      * For an L1, L5 receiver tracking a satellite on L1 and L5 at the same time, two measurements
      * will be reported for this same satellite, in one all the values related to L1 will be
      * filled, and in the other all of the values related to L5 will be filled.
      *
      * <p>The value is only available if {@link #hasCarrierFrequencyHz(int satelliteIndex)} is
      * {@code true}.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     @FloatRange(from = 0)
     public float getCarrierFrequencyHz(@IntRange(from = 0) int satelliteIndex) {
         return mCarrierFrequencies[satelliteIndex];
     }

     /**
      * Reports whether a valid {@link #getBasebandCn0DbHz(int satelliteIndex)} is available.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     public boolean hasBasebandCn0DbHz(@IntRange(from = 0) int satelliteIndex) {
         return (mSvidWithFlags[satelliteIndex] & SVID_FLAGS_HAS_BASEBAND_CN0) != 0;
     }

     /**
      * Retrieves the baseband carrier-to-noise density of the satellite at the specified index in
      * dB-Hz.
      *
      * @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
      */
     @FloatRange(from = 0, to = 63)
     public float getBasebandCn0DbHz(@IntRange(from = 0) int satelliteIndex) {
         return mBasebandCn0DbHzs[satelliteIndex];
     }

     /**
      * Returns the string representation of a constellation type.
      *
      * @param constellationType the constellation type.
      * @return the string representation.
      * @hide
      */
     @NonNull
     public static String constellationTypeToString(@ConstellationType int constellationType) {
         switch (constellationType) {
             case CONSTELLATION_UNKNOWN:
                 return "UNKNOWN";
             case CONSTELLATION_GPS:
                 return "GPS";
             case CONSTELLATION_SBAS:
                 return "SBAS";
             case CONSTELLATION_GLONASS:
                 return "GLONASS";
             case CONSTELLATION_QZSS:
                 return "QZSS";
             case CONSTELLATION_BEIDOU:
                 return "BEIDOU";
             case CONSTELLATION_GALILEO:
                 return "GALILEO";
             case CONSTELLATION_IRNSS:
                 return "IRNSS";
             default:
                 return Integer.toString(constellationType);
         }
     }

     @Override
     public boolean equals(Object o) {
         if (this == o) {
             return true;
         }
         if (!(o instanceof GnssStatus)) {
             return false;
         }

         GnssStatus that = (GnssStatus) o;
         return mSvCount == that.mSvCount
                 && Arrays.equals(mSvidWithFlags, that.mSvidWithFlags)
                 && Arrays.equals(mCn0DbHzs, that.mCn0DbHzs)
                 && Arrays.equals(mElevations, that.mElevations)
                 && Arrays.equals(mAzimuths, that.mAzimuths)
                 && Arrays.equals(mCarrierFrequencies, that.mCarrierFrequencies)
                 && Arrays.equals(mBasebandCn0DbHzs, that.mBasebandCn0DbHzs);
     }

     @Override
     public int hashCode() {
         int result = Objects.hash(mSvCount);
         result = 31 * result + Arrays.hashCode(mSvidWithFlags);
         result = 31 * result + Arrays.hashCode(mCn0DbHzs);
         return result;
     }

     public static final @NonNull Creator<GnssStatus> CREATOR = new Creator<GnssStatus>() {
         @Override
         public GnssStatus createFromParcel(Parcel in) {
             int svCount = in.readInt();
             int[] svidWithFlags = new int[svCount];
             float[] cn0DbHzs = new float[svCount];
             float[] elevations = new float[svCount];
             float[] azimuths = new float[svCount];
             float[] carrierFrequencies = new float[svCount];
             float[] basebandCn0DbHzs = new float[svCount];
             for (int i = 0; i < svCount; i++) {
                 svidWithFlags[i] = in.readInt();
             }
             for (int i = 0; i < svCount; i++) {
                 cn0DbHzs[i] = in.readFloat();
             }
             for (int i = 0; i < svCount; i++) {
                 elevations[i] = in.readFloat();
             }
             for (int i = 0; i < svCount; i++) {
                 azimuths[i] = in.readFloat();
             }
             for (int i = 0; i < svCount; i++) {
                 carrierFrequencies[i] = in.readFloat();
             }
             for (int i = 0; i < svCount; i++) {
                 basebandCn0DbHzs[i] = in.readFloat();
             }

             return new GnssStatus(svCount, svidWithFlags, cn0DbHzs, elevations, azimuths,
                     carrierFrequencies, basebandCn0DbHzs);
         }

         @Override
         public GnssStatus[] newArray(int size) {
             return new GnssStatus[size];
         }
     };

     @Override
     public int describeContents() {
         return 0;
     }

     @Override
     public void writeToParcel(@NonNull Parcel parcel, int flags) {
         parcel.writeInt(mSvCount);
         for (int i = 0; i < mSvCount; i++) {
             parcel.writeInt(mSvidWithFlags[i]);
         }
         for (int i = 0; i < mSvCount; i++) {
             parcel.writeFloat(mCn0DbHzs[i]);
         }
         for (int i = 0; i < mSvCount; i++) {
             parcel.writeFloat(mElevations[i]);
         }
         for (int i = 0; i < mSvCount; i++) {
             parcel.writeFloat(mAzimuths[i]);
         }
         for (int i = 0; i < mSvCount; i++) {
             parcel.writeFloat(mCarrierFrequencies[i]);
         }
         for (int i = 0; i < mSvCount; i++) {
             parcel.writeFloat(mBasebandCn0DbHzs[i]);
         }
     }

     /**
      * Builder class to help create new GnssStatus instances.
      */
     public static final class Builder {

         private final ArrayList<GnssSvInfo> mSatellites = new ArrayList<>();

         /**
          * Adds a new satellite to the Builder.
          *
          * @param constellationType one of the CONSTELLATION_* constants
          * @param svid the space vehicle identifier
          * @param cn0DbHz carrier-to-noise density at the antenna in dB-Hz
          * @param elevation satellite elevation in degrees
          * @param azimuth satellite azimuth in degrees
          * @param hasEphemeris whether the satellite has ephemeris data
          * @param hasAlmanac whether the satellite has almanac data
          * @param usedInFix whether the satellite was used in the most recent location fix
          * @param hasCarrierFrequency whether carrier frequency data is available
          * @param carrierFrequency satellite carrier frequency in Hz
          * @param hasBasebandCn0DbHz whether baseband carrier-to-noise density is available
          * @param basebandCn0DbHz baseband carrier-to-noise density in dB-Hz
          */
         @NonNull
         public Builder addSatellite(@ConstellationType int constellationType,
                 @IntRange(from = 1, to = 200) int svid,
                 @FloatRange(from = 0, to = 63) float cn0DbHz,
                 @FloatRange(from = -90, to = 90) float elevation,
                 @FloatRange(from = 0, to = 360) float azimuth,
                 boolean hasEphemeris,
                 boolean hasAlmanac,
                 boolean usedInFix,
                 boolean hasCarrierFrequency,
                 @FloatRange(from = 0) float carrierFrequency,
                 boolean hasBasebandCn0DbHz,
                 @FloatRange(from = 0, to = 63) float basebandCn0DbHz) {
             mSatellites.add(new GnssSvInfo(constellationType, svid, cn0DbHz, elevation, azimuth,
                     hasEphemeris, hasAlmanac, usedInFix, hasCarrierFrequency, carrierFrequency,
                     hasBasebandCn0DbHz, basebandCn0DbHz));
             return this;
         }

         /**
          * Clears all satellites in the Builder.
          */
         @NonNull
         public Builder clearSatellites() {
             mSatellites.clear();
             return this;
         }

         /**
          * Builds a new GnssStatus based on the satellite information in the Builder.
          */
         @NonNull
         public GnssStatus build() {
             int svCount = mSatellites.size();
             int[] svidWithFlags = new int[svCount];
             float[] cn0DbHzs = new float[svCount];
             float[] elevations = new float[svCount];
             float[] azimuths = new float[svCount];
             float[] carrierFrequencies = new float[svCount];
             float[] basebandCn0DbHzs = new float[svCount];

             for (int i = 0; i < svidWithFlags.length; i++) {
                 svidWithFlags[i] = mSatellites.get(i).mSvidWithFlags;
             }
             for (int i = 0; i < cn0DbHzs.length; i++) {
                 cn0DbHzs[i] = mSatellites.get(i).mCn0DbHz;
             }
             for (int i = 0; i < elevations.length; i++) {
                 elevations[i] = mSatellites.get(i).mElevation;
             }
             for (int i = 0; i < azimuths.length; i++) {
                 azimuths[i] = mSatellites.get(i).mAzimuth;
             }
             for (int i = 0; i < carrierFrequencies.length; i++) {
                 carrierFrequencies[i] = mSatellites.get(i).mCarrierFrequency;
             }
             for (int i = 0; i < basebandCn0DbHzs.length; i++) {
                 basebandCn0DbHzs[i] = mSatellites.get(i).mBasebandCn0DbHz;
             }

             return new GnssStatus(svCount, svidWithFlags, cn0DbHzs, elevations, azimuths,
                     carrierFrequencies, basebandCn0DbHzs);
         }
     }

     private static class GnssSvInfo {

         private final int mSvidWithFlags;
         private final float mCn0DbHz;
         private final float mElevation;
         private final float mAzimuth;
         private final float mCarrierFrequency;
         private final float mBasebandCn0DbHz;

         private GnssSvInfo(int constellationType, int svid, float cn0DbHz,
                 float elevation, float azimuth, boolean hasEphemeris, boolean hasAlmanac,
                 boolean usedInFix, boolean hasCarrierFrequency, float carrierFrequency,
                 boolean hasBasebandCn0DbHz, float basebandCn0DbHz) {
             mSvidWithFlags = (svid << SVID_SHIFT_WIDTH)
                     | ((constellationType & CONSTELLATION_TYPE_MASK)
                     << CONSTELLATION_TYPE_SHIFT_WIDTH)
                     | (hasEphemeris ? SVID_FLAGS_HAS_EPHEMERIS_DATA : SVID_FLAGS_NONE)
                     | (hasAlmanac ? SVID_FLAGS_HAS_ALMANAC_DATA : SVID_FLAGS_NONE)
                     | (usedInFix ? SVID_FLAGS_USED_IN_FIX : SVID_FLAGS_NONE)
                     | (hasCarrierFrequency ? SVID_FLAGS_HAS_CARRIER_FREQUENCY : SVID_FLAGS_NONE)
                     | (hasBasebandCn0DbHz ? SVID_FLAGS_HAS_BASEBAND_CN0 : SVID_FLAGS_NONE);
             mCn0DbHz = cn0DbHz;
             mElevation = elevation;
             mAzimuth = azimuth;
             mCarrierFrequency = hasCarrierFrequency ? carrierFrequency : 0;
             mBasebandCn0DbHz = hasBasebandCn0DbHz ? basebandCn0DbHz : 0;
         }
     }
 }
	/*
	* Copyright (C) 2016 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package android.location;

	import android.annotation.FloatRange;
	import android.annotation.IntDef;
	import android.annotation.IntRange;
	import android.annotation.NonNull;
	import android.os.Parcel;
	import android.os.Parcelable;

	import com.android.internal.util.Preconditions;

	import java.lang.annotation.Retention;
	import java.lang.annotation.RetentionPolicy;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.Objects;

	/**
	* This class represents the current state of the GNSS engine and is used in conjunction with
	* {@link GnssStatus.Callback}.
	*
	* @see LocationManager#registerGnssStatusCallback
	* @see GnssStatus.Callback
	*/
	public final class GnssStatus implements Parcelable {

	// These must match the definitions in GNSS HAL.
	//
	// Note: these constants are also duplicated in GnssStatusCompat.java in the androidx support
	// library. if adding a constellation, please update that file as well.

	/** Unknown constellation type. */
	public static final int CONSTELLATION_UNKNOWN = 0;
	/** Constellation type constant for GPS. */
	public static final int CONSTELLATION_GPS = 1;
	/** Constellation type constant for SBAS. */
	public static final int CONSTELLATION_SBAS = 2;
	/** Constellation type constant for Glonass. */
	public static final int CONSTELLATION_GLONASS = 3;
	/** Constellation type constant for QZSS. */
	public static final int CONSTELLATION_QZSS = 4;
	/** Constellation type constant for Beidou. */
	public static final int CONSTELLATION_BEIDOU = 5;
	/** Constellation type constant for Galileo. */
	public static final int CONSTELLATION_GALILEO = 6;
	/** Constellation type constant for IRNSS. */
	public static final int CONSTELLATION_IRNSS = 7;
	/** @hide */
	public static final int CONSTELLATION_COUNT = 8;

	private static final int SVID_FLAGS_NONE = 0;
	private static final int SVID_FLAGS_HAS_EPHEMERIS_DATA = (1 << 0);
	private static final int SVID_FLAGS_HAS_ALMANAC_DATA = (1 << 1);
	private static final int SVID_FLAGS_USED_IN_FIX = (1 << 2);
	private static final int SVID_FLAGS_HAS_CARRIER_FREQUENCY = (1 << 3);
	private static final int SVID_FLAGS_HAS_BASEBAND_CN0 = (1 << 4);

	private static final int SVID_SHIFT_WIDTH = 12;
	private static final int CONSTELLATION_TYPE_SHIFT_WIDTH = 8;
	private static final int CONSTELLATION_TYPE_MASK = 0xf;

	/**
	* Used for receiving notifications when GNSS events happen.
	*
	* @see LocationManager#registerGnssStatusCallback
	*/
	public static abstract class Callback {
	/**
	* Called when GNSS system has started.
	*/
	public void onStarted() {
	}

	/**
	* Called when GNSS system has stopped.
	*/
	public void onStopped() {
	}

	/**
	* Called when the GNSS system has received its first fix since starting.
	*
	* @param ttffMillis the time from start to first fix in milliseconds.
	*/
	public void onFirstFix(int ttffMillis) {
	}

	/**
	* Called periodically to report GNSS satellite status.
	*
	* @param status the current status of all satellites.
	*/
	public void onSatelliteStatusChanged(@NonNull GnssStatus status) {
	}
	}

	/**
	* Constellation type.
	*
	* @hide
	*/
	@Retention(RetentionPolicy.SOURCE)
	@IntDef({CONSTELLATION_UNKNOWN, CONSTELLATION_GPS, CONSTELLATION_SBAS, CONSTELLATION_GLONASS,
	CONSTELLATION_QZSS, CONSTELLATION_BEIDOU, CONSTELLATION_GALILEO, CONSTELLATION_IRNSS})
	public @interface ConstellationType {
	}

	/**
	* Create a GnssStatus that wraps the given arguments without any additional overhead. Callers
	* are responsible for guaranteeing that the arguments are never modified after calling this
	* method.
	*
	* @hide
	*/
	@NonNull
	public static GnssStatus wrap(int svCount, int[] svidWithFlags, float[] cn0DbHzs,
	float[] elevations, float[] azimuths, float[] carrierFrequencies,
	float[] basebandCn0DbHzs) {
	Preconditions.checkState(svCount >= 0);
	Preconditions.checkState(svidWithFlags.length >= svCount);
	Preconditions.checkState(elevations.length >= svCount);
	Preconditions.checkState(azimuths.length >= svCount);
	Preconditions.checkState(carrierFrequencies.length >= svCount);
	Preconditions.checkState(basebandCn0DbHzs.length >= svCount);

	return new GnssStatus(svCount, svidWithFlags, cn0DbHzs, elevations, azimuths,
	carrierFrequencies, basebandCn0DbHzs);
	}

	private final int mSvCount;
	private final int[] mSvidWithFlags;
	private final float[] mCn0DbHzs;
	private final float[] mElevations;
	private final float[] mAzimuths;
	private final float[] mCarrierFrequencies;
	private final float[] mBasebandCn0DbHzs;

	private GnssStatus(int svCount, int[] svidWithFlags, float[] cn0DbHzs, float[] elevations,
	float[] azimuths, float[] carrierFrequencies, float[] basebandCn0DbHzs) {
	mSvCount = svCount;
	mSvidWithFlags = svidWithFlags;
	mCn0DbHzs = cn0DbHzs;
	mElevations = elevations;
	mAzimuths = azimuths;
	mCarrierFrequencies = carrierFrequencies;
	mBasebandCn0DbHzs = basebandCn0DbHzs;
	}

	/**
	* Gets the total number of satellites in satellite list.
	*/
	@IntRange(from = 0)
	public int getSatelliteCount() {
	return mSvCount;
	}

	/**
	* Retrieves the constellation type of the satellite at the specified index.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	@ConstellationType
	public int getConstellationType(@IntRange(from = 0) int satelliteIndex) {
	return ((mSvidWithFlags[satelliteIndex] >> CONSTELLATION_TYPE_SHIFT_WIDTH)
	& CONSTELLATION_TYPE_MASK);
	}

	/**
	* Gets the identification number for the satellite at the specific index.
	*
	* <p>This svid is pseudo-random number for most constellations. It is FCN & OSN number for
	* Glonass.
	*
	* <p>The distinction is made by looking at constellation field
	* {@link #getConstellationType(int)} Expected values are in the range of:
	*
	* <ul>
	* <li>GPS: 1-32</li>
	* <li>SBAS: 120-151, 183-192</li>
	* <li>GLONASS: One of: OSN, or FCN+100
	* <ul>
	* <li>1-24 as the orbital slot number (OSN) (preferred, if known)</li>
	* <li>93-106 as the frequency channel number (FCN) (-7 to +6) plus 100.
	* i.e. encode FCN of -7 as 93, 0 as 100, and +6 as 106</li>
	* </ul></li>
	* <li>QZSS: 193-200</li>
	* <li>Galileo: 1-36</li>
	* <li>Beidou: 1-37</li>
	* <li>IRNSS: 1-14</li>
	* </ul>
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	@IntRange(from = 1, to = 200)
	public int getSvid(@IntRange(from = 0) int satelliteIndex) {
	return mSvidWithFlags[satelliteIndex] >> SVID_SHIFT_WIDTH;
	}

	/**
	* Retrieves the carrier-to-noise density at the antenna of the satellite at the specified index
	* in dB-Hz.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	@FloatRange(from = 0, to = 63)
	public float getCn0DbHz(@IntRange(from = 0) int satelliteIndex) {
	return mCn0DbHzs[satelliteIndex];
	}

	/**
	* Retrieves the elevation of the satellite at the specified index.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	@FloatRange(from = -90, to = 90)
	public float getElevationDegrees(@IntRange(from = 0) int satelliteIndex) {
	return mElevations[satelliteIndex];
	}

	/**
	* Retrieves the azimuth the satellite at the specified index.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	@FloatRange(from = 0, to = 360)
	public float getAzimuthDegrees(@IntRange(from = 0) int satelliteIndex) {
	return mAzimuths[satelliteIndex];
	}

	/**
	* Reports whether the satellite at the specified index has ephemeris data.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	public boolean hasEphemerisData(@IntRange(from = 0) int satelliteIndex) {
	return (mSvidWithFlags[satelliteIndex] & SVID_FLAGS_HAS_EPHEMERIS_DATA) != 0;
	}

	/**
	* Reports whether the satellite at the specified index has almanac data.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	public boolean hasAlmanacData(@IntRange(from = 0) int satelliteIndex) {
	return (mSvidWithFlags[satelliteIndex] & SVID_FLAGS_HAS_ALMANAC_DATA) != 0;
	}

	/**
	* Reports whether the satellite at the specified index was used in the calculation of the most
	* recent position fix.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	public boolean usedInFix(@IntRange(from = 0) int satelliteIndex) {
	return (mSvidWithFlags[satelliteIndex] & SVID_FLAGS_USED_IN_FIX) != 0;
	}

	/**
	* Reports whether a valid {@link #getCarrierFrequencyHz(int satelliteIndex)} is available.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	public boolean hasCarrierFrequencyHz(@IntRange(from = 0) int satelliteIndex) {
	return (mSvidWithFlags[satelliteIndex] & SVID_FLAGS_HAS_CARRIER_FREQUENCY) != 0;
	}

	/**
	* Gets the carrier frequency of the signal tracked.
	*
	* <p>For example it can be the GPS central frequency for L1 = 1575.45 MHz, or L2 = 1227.60
	* MHz, L5 = 1176.45 MHz, varying GLO channels, etc. If the field is not set, it is the primary
	* common use central frequency, e.g. L1 = 1575.45 MHz for GPS.
	*
	* For an L1, L5 receiver tracking a satellite on L1 and L5 at the same time, two measurements
	* will be reported for this same satellite, in one all the values related to L1 will be
	* filled, and in the other all of the values related to L5 will be filled.
	*
	* <p>The value is only available if {@link #hasCarrierFrequencyHz(int satelliteIndex)} is
	* {@code true}.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	@FloatRange(from = 0)
	public float getCarrierFrequencyHz(@IntRange(from = 0) int satelliteIndex) {
	return mCarrierFrequencies[satelliteIndex];
	}

	/**
	* Reports whether a valid {@link #getBasebandCn0DbHz(int satelliteIndex)} is available.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	public boolean hasBasebandCn0DbHz(@IntRange(from = 0) int satelliteIndex) {
	return (mSvidWithFlags[satelliteIndex] & SVID_FLAGS_HAS_BASEBAND_CN0) != 0;
	}

	/**
	* Retrieves the baseband carrier-to-noise density of the satellite at the specified index in
	* dB-Hz.
	*
	* @param satelliteIndex An index from zero to {@link #getSatelliteCount()} - 1
	*/
	@FloatRange(from = 0, to = 63)
	public float getBasebandCn0DbHz(@IntRange(from = 0) int satelliteIndex) {
	return mBasebandCn0DbHzs[satelliteIndex];
	}

	/**
	* Returns the string representation of a constellation type.
	*
	* @param constellationType the constellation type.
	* @return the string representation.
	* @hide
	*/
	@NonNull
	public static String constellationTypeToString(@ConstellationType int constellationType) {
	switch (constellationType) {
	case CONSTELLATION_UNKNOWN:
	return "UNKNOWN";
	case CONSTELLATION_GPS:
	return "GPS";
	case CONSTELLATION_SBAS:
	return "SBAS";
	case CONSTELLATION_GLONASS:
	return "GLONASS";
	case CONSTELLATION_QZSS:
	return "QZSS";
	case CONSTELLATION_BEIDOU:
	return "BEIDOU";
	case CONSTELLATION_GALILEO:
	return "GALILEO";
	case CONSTELLATION_IRNSS:
	return "IRNSS";
	default:
	return Integer.toString(constellationType);
	}
	}

	@Override
	public boolean equals(Object o) {
	if (this == o) {
	return true;
	}
	if (!(o instanceof GnssStatus)) {
	return false;
	}

	GnssStatus that = (GnssStatus) o;
	return mSvCount == that.mSvCount
	&& Arrays.equals(mSvidWithFlags, that.mSvidWithFlags)
	&& Arrays.equals(mCn0DbHzs, that.mCn0DbHzs)
	&& Arrays.equals(mElevations, that.mElevations)
	&& Arrays.equals(mAzimuths, that.mAzimuths)
	&& Arrays.equals(mCarrierFrequencies, that.mCarrierFrequencies)
	&& Arrays.equals(mBasebandCn0DbHzs, that.mBasebandCn0DbHzs);
	}

	@Override
	public int hashCode() {
	int result = Objects.hash(mSvCount);
	result = 31 * result + Arrays.hashCode(mSvidWithFlags);
	result = 31 * result + Arrays.hashCode(mCn0DbHzs);
	return result;
	}

	public static final @NonNull Creator<GnssStatus> CREATOR = new Creator<GnssStatus>() {
	@Override
	public GnssStatus createFromParcel(Parcel in) {
	int svCount = in.readInt();
	int[] svidWithFlags = new int[svCount];
	float[] cn0DbHzs = new float[svCount];
	float[] elevations = new float[svCount];
	float[] azimuths = new float[svCount];
	float[] carrierFrequencies = new float[svCount];
	float[] basebandCn0DbHzs = new float[svCount];
	for (int i = 0; i < svCount; i++) {
	svidWithFlags[i] = in.readInt();
	}
	for (int i = 0; i < svCount; i++) {
	cn0DbHzs[i] = in.readFloat();
	}
	for (int i = 0; i < svCount; i++) {
	elevations[i] = in.readFloat();
	}
	for (int i = 0; i < svCount; i++) {
	azimuths[i] = in.readFloat();
	}
	for (int i = 0; i < svCount; i++) {
	carrierFrequencies[i] = in.readFloat();
	}
	for (int i = 0; i < svCount; i++) {
	basebandCn0DbHzs[i] = in.readFloat();
	}

	return new GnssStatus(svCount, svidWithFlags, cn0DbHzs, elevations, azimuths,
	carrierFrequencies, basebandCn0DbHzs);
	}

	@Override
	public GnssStatus[] newArray(int size) {
	return new GnssStatus[size];
	}
	};

	@Override
	public int describeContents() {
	return 0;
	}

	@Override
	public void writeToParcel(@NonNull Parcel parcel, int flags) {
	parcel.writeInt(mSvCount);
	for (int i = 0; i < mSvCount; i++) {
	parcel.writeInt(mSvidWithFlags[i]);
	}
	for (int i = 0; i < mSvCount; i++) {
	parcel.writeFloat(mCn0DbHzs[i]);
	}
	for (int i = 0; i < mSvCount; i++) {
	parcel.writeFloat(mElevations[i]);
	}
	for (int i = 0; i < mSvCount; i++) {
	parcel.writeFloat(mAzimuths[i]);
	}
	for (int i = 0; i < mSvCount; i++) {
	parcel.writeFloat(mCarrierFrequencies[i]);
	}
	for (int i = 0; i < mSvCount; i++) {
	parcel.writeFloat(mBasebandCn0DbHzs[i]);
	}
	}

	/**
	* Builder class to help create new GnssStatus instances.
	*/
	public static final class Builder {

	private final ArrayList<GnssSvInfo> mSatellites = new ArrayList<>();

	/**
	* Adds a new satellite to the Builder.
	*
	* @param constellationType one of the CONSTELLATION_* constants
	* @param svid the space vehicle identifier
	* @param cn0DbHz carrier-to-noise density at the antenna in dB-Hz
	* @param elevation satellite elevation in degrees
	* @param azimuth satellite azimuth in degrees
	* @param hasEphemeris whether the satellite has ephemeris data
	* @param hasAlmanac whether the satellite has almanac data
	* @param usedInFix whether the satellite was used in the most recent location fix
	* @param hasCarrierFrequency whether carrier frequency data is available
	* @param carrierFrequency satellite carrier frequency in Hz
	* @param hasBasebandCn0DbHz whether baseband carrier-to-noise density is available
	* @param basebandCn0DbHz baseband carrier-to-noise density in dB-Hz
	*/
	@NonNull
	public Builder addSatellite(@ConstellationType int constellationType,
	@IntRange(from = 1, to = 200) int svid,
	@FloatRange(from = 0, to = 63) float cn0DbHz,
	@FloatRange(from = -90, to = 90) float elevation,
	@FloatRange(from = 0, to = 360) float azimuth,
	boolean hasEphemeris,
	boolean hasAlmanac,
	boolean usedInFix,
	boolean hasCarrierFrequency,
	@FloatRange(from = 0) float carrierFrequency,
	boolean hasBasebandCn0DbHz,
	@FloatRange(from = 0, to = 63) float basebandCn0DbHz) {
	mSatellites.add(new GnssSvInfo(constellationType, svid, cn0DbHz, elevation, azimuth,
	hasEphemeris, hasAlmanac, usedInFix, hasCarrierFrequency, carrierFrequency,
	hasBasebandCn0DbHz, basebandCn0DbHz));
	return this;
	}

	/**
	* Clears all satellites in the Builder.
	*/
	@NonNull
	public Builder clearSatellites() {
	mSatellites.clear();
	return this;
	}

	/**
	* Builds a new GnssStatus based on the satellite information in the Builder.
	*/
	@NonNull
	public GnssStatus build() {
	int svCount = mSatellites.size();
	int[] svidWithFlags = new int[svCount];
	float[] cn0DbHzs = new float[svCount];
	float[] elevations = new float[svCount];
	float[] azimuths = new float[svCount];
	float[] carrierFrequencies = new float[svCount];
	float[] basebandCn0DbHzs = new float[svCount];

	for (int i = 0; i < svidWithFlags.length; i++) {
	svidWithFlags[i] = mSatellites.get(i).mSvidWithFlags;
	}
	for (int i = 0; i < cn0DbHzs.length; i++) {
	cn0DbHzs[i] = mSatellites.get(i).mCn0DbHz;
	}
	for (int i = 0; i < elevations.length; i++) {
	elevations[i] = mSatellites.get(i).mElevation;
	}
	for (int i = 0; i < azimuths.length; i++) {
	azimuths[i] = mSatellites.get(i).mAzimuth;
	}
	for (int i = 0; i < carrierFrequencies.length; i++) {
	carrierFrequencies[i] = mSatellites.get(i).mCarrierFrequency;
	}
	for (int i = 0; i < basebandCn0DbHzs.length; i++) {
	basebandCn0DbHzs[i] = mSatellites.get(i).mBasebandCn0DbHz;
	}

	return new GnssStatus(svCount, svidWithFlags, cn0DbHzs, elevations, azimuths,
	carrierFrequencies, basebandCn0DbHzs);
	}
	}

	private static class GnssSvInfo {

	private final int mSvidWithFlags;
	private final float mCn0DbHz;
	private final float mElevation;
	private final float mAzimuth;
	private final float mCarrierFrequency;
	private final float mBasebandCn0DbHz;

	private GnssSvInfo(int constellationType, int svid, float cn0DbHz,
	float elevation, float azimuth, boolean hasEphemeris, boolean hasAlmanac,
	boolean usedInFix, boolean hasCarrierFrequency, float carrierFrequency,
	boolean hasBasebandCn0DbHz, float basebandCn0DbHz) {
	mSvidWithFlags = (svid << SVID_SHIFT_WIDTH)
	\| ((constellationType & CONSTELLATION_TYPE_MASK)
	<< CONSTELLATION_TYPE_SHIFT_WIDTH)
	\| (hasEphemeris ? SVID_FLAGS_HAS_EPHEMERIS_DATA : SVID_FLAGS_NONE)
	\| (hasAlmanac ? SVID_FLAGS_HAS_ALMANAC_DATA : SVID_FLAGS_NONE)
	\| (usedInFix ? SVID_FLAGS_USED_IN_FIX : SVID_FLAGS_NONE)
	\| (hasCarrierFrequency ? SVID_FLAGS_HAS_CARRIER_FREQUENCY : SVID_FLAGS_NONE)
	\| (hasBasebandCn0DbHz ? SVID_FLAGS_HAS_BASEBAND_CN0 : SVID_FLAGS_NONE);
	mCn0DbHz = cn0DbHz;
	mElevation = elevation;
	mAzimuth = azimuth;
	mCarrierFrequency = hasCarrierFrequency ? carrierFrequency : 0;
	mBasebandCn0DbHz = hasBasebandCn0DbHz ? basebandCn0DbHz : 0;
	}
	}
	}