Java tutorial
/* * Copyright (C) 2014 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.TestApi; import android.annotation.IntDef; import android.annotation.NonNull; import android.os.Parcel; import android.os.Parcelable; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.security.InvalidParameterException; import java.util.Arrays; import java.util.Collection; import java.util.Collections; /** * A class implementing a container for data associated with a measurement event. * Events are delivered to registered instances of {@link Callback}. */ public final class GnssMeasurementsEvent implements Parcelable { private final GnssClock mClock; private final Collection<GnssMeasurement> mReadOnlyMeasurements; /** * Used for receiving GNSS satellite measurements from the GNSS engine. * Each measurement contains raw and computed data identifying a satellite. * You can implement this interface and call * {@link LocationManager#registerGnssMeasurementsCallback}. */ public static abstract class Callback { /** * The status of the GNSS measurements event. * @hide */ @Retention(RetentionPolicy.SOURCE) @IntDef({ STATUS_NOT_SUPPORTED, STATUS_READY, STATUS_LOCATION_DISABLED, STATUS_NOT_ALLOWED }) public @interface GnssMeasurementsStatus { } /** * The system does not support tracking of GNSS Measurements. * * <p>This status will not change in the future. */ public static final int STATUS_NOT_SUPPORTED = 0; /** * GNSS Measurements are successfully being tracked, it will receive updates once they are * available. */ public static final int STATUS_READY = 1; /** * GPS provider or Location is disabled, updates will not be received until they are * enabled. */ public static final int STATUS_LOCATION_DISABLED = 2; /** * The client is not allowed to register for GNSS Measurements in general or in the * requested mode. * * <p>Such a status is returned when a client tries to request a functionality from the GNSS * chipset while another client has an ongoing request that does not allow such * functionality to be performed. * * <p>If such a status is received, one would try again at a later time point where no * other client is having a conflicting request. */ public static final int STATUS_NOT_ALLOWED = 3; /** * Reports the latest collected GNSS Measurements. */ public void onGnssMeasurementsReceived(GnssMeasurementsEvent eventArgs) { } /** * Reports the latest status of the GNSS Measurements sub-system. */ public void onStatusChanged(@GnssMeasurementsStatus int status) { } } /** * @hide */ @TestApi public GnssMeasurementsEvent(GnssClock clock, GnssMeasurement[] measurements) { if (clock == null) { throw new InvalidParameterException("Parameter 'clock' must not be null."); } if (measurements == null || measurements.length == 0) { mReadOnlyMeasurements = Collections.emptyList(); } else { Collection<GnssMeasurement> measurementCollection = Arrays.asList(measurements); mReadOnlyMeasurements = Collections.unmodifiableCollection(measurementCollection); } mClock = clock; } /** * Gets the GNSS receiver clock information associated with the measurements for the current * event. */ @NonNull public GnssClock getClock() { return mClock; } /** * Gets a read-only collection of measurements associated with the current event. */ @NonNull public Collection<GnssMeasurement> getMeasurements() { return mReadOnlyMeasurements; } public static final Creator<GnssMeasurementsEvent> CREATOR = new Creator<GnssMeasurementsEvent>() { @Override public GnssMeasurementsEvent createFromParcel(Parcel in) { ClassLoader classLoader = getClass().getClassLoader(); GnssClock clock = in.readParcelable(classLoader); int measurementsLength = in.readInt(); GnssMeasurement[] measurementsArray = new GnssMeasurement[measurementsLength]; in.readTypedArray(measurementsArray, GnssMeasurement.CREATOR); return new GnssMeasurementsEvent(clock, measurementsArray); } @Override public GnssMeasurementsEvent[] newArray(int size) { return new GnssMeasurementsEvent[size]; } }; @Override public int describeContents() { return 0; } @Override public void writeToParcel(Parcel parcel, int flags) { parcel.writeParcelable(mClock, flags); int measurementsCount = mReadOnlyMeasurements.size(); GnssMeasurement[] measurementsArray = mReadOnlyMeasurements.toArray(new GnssMeasurement[measurementsCount]); parcel.writeInt(measurementsArray.length); parcel.writeTypedArray(measurementsArray, flags); } @Override public String toString() { StringBuilder builder = new StringBuilder("[ GnssMeasurementsEvent:\n\n"); builder.append(mClock.toString()); builder.append("\n"); for (GnssMeasurement measurement : mReadOnlyMeasurements) { builder.append(measurement.toString()); builder.append("\n"); } builder.append("]"); return builder.toString(); } }