Merge "Hold a strong reference to the callback in TextClassifierService" into qt-qpr1-dev
diff --git a/services/core/java/com/android/server/notification/PreferencesHelper.java b/services/core/java/com/android/server/notification/PreferencesHelper.java
index 7b45a1b..669dce7 100644
--- a/services/core/java/com/android/server/notification/PreferencesHelper.java
+++ b/services/core/java/com/android/server/notification/PreferencesHelper.java
@@ -73,6 +73,9 @@
     private static final String NON_BLOCKABLE_CHANNEL_DELIM = ":";
 
     @VisibleForTesting
+    static final int NOTIFICATION_CHANNEL_COUNT_LIMIT = 5000;
+
+    @VisibleForTesting
     static final String TAG_RANKING = "ranking";
     private static final String TAG_PACKAGE = "package";
     private static final String TAG_CHANNEL = "channel";
@@ -179,6 +182,7 @@
                                     // noop
                                 }
                             }
+                            boolean skipWarningLogged = false;
 
                             PackagePreferences r = getOrCreatePackagePreferencesLocked(name, uid,
                                     XmlUtils.readIntAttribute(
@@ -225,6 +229,14 @@
                                 }
                                 // Channels
                                 if (TAG_CHANNEL.equals(tagName)) {
+                                    if (r.channels.size() >= NOTIFICATION_CHANNEL_COUNT_LIMIT) {
+                                        if (!skipWarningLogged) {
+                                            Slog.w(TAG, "Skipping further channels for " + r.pkg
+                                                    + "; app has too many");
+                                            skipWarningLogged = true;
+                                        }
+                                        continue;
+                                    }
                                     String id = parser.getAttributeValue(null, ATT_ID);
                                     String channelName = parser.getAttributeValue(null, ATT_NAME);
                                     int channelImportance = XmlUtils.readIntAttribute(
@@ -690,6 +702,10 @@
                 return needsPolicyFileChange;
             }
 
+            if (r.channels.size() >= NOTIFICATION_CHANNEL_COUNT_LIMIT) {
+                throw new IllegalStateException("Limit exceed; cannot create more channels");
+            }
+
             needsPolicyFileChange = true;
 
             if (channel.getImportance() < IMPORTANCE_NONE
diff --git a/services/core/java/com/android/server/policy/role/LegacyRoleResolutionPolicy.java b/services/core/java/com/android/server/policy/role/LegacyRoleResolutionPolicy.java
index 77bf930..712012d 100644
--- a/services/core/java/com/android/server/policy/role/LegacyRoleResolutionPolicy.java
+++ b/services/core/java/com/android/server/policy/role/LegacyRoleResolutionPolicy.java
@@ -24,20 +24,17 @@
 import android.content.pm.PackageManager;
 import android.content.pm.PackageManagerInternal;
 import android.content.pm.ResolveInfo;
-import android.os.Debug;
 import android.provider.Settings;
-import android.telecom.TelecomManager;
 import android.text.TextUtils;
-import android.util.Log;
 import android.util.Slog;
 
+import com.android.internal.R;
 import com.android.internal.telephony.SmsApplication;
 import com.android.internal.util.CollectionUtils;
 import com.android.server.LocalServices;
 import com.android.server.role.RoleManagerService;
 
 import java.util.ArrayList;
-import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 
@@ -67,14 +64,25 @@
     public List<String> getRoleHolders(@NonNull String roleName, @UserIdInt int userId) {
         switch (roleName) {
             case RoleManager.ROLE_ASSISTANT: {
-                String legacyAssistant = Settings.Secure.getStringForUser(
-                        mContext.getContentResolver(), Settings.Secure.ASSISTANT, userId);
-                if (legacyAssistant == null || legacyAssistant.isEmpty()) {
-                    return Collections.emptyList();
+                String packageName;
+                String setting = Settings.Secure.getStringForUser(mContext.getContentResolver(),
+                        Settings.Secure.ASSISTANT, userId);
+                // AssistUtils was using the default assistant app if Settings.Secure.ASSISTANT is
+                // null, while only an empty string means user selected "None".
+                if (setting != null) {
+                    if (!setting.isEmpty()) {
+                        ComponentName componentName = ComponentName.unflattenFromString(setting);
+                        packageName = componentName != null ? componentName.getPackageName() : null;
+                    } else {
+                        packageName = null;
+                    }
+                } else if (mContext.getPackageManager().isDeviceUpgrading()) {
+                    String defaultAssistant = mContext.getString(R.string.config_defaultAssistant);
+                    packageName = !TextUtils.isEmpty(defaultAssistant) ? defaultAssistant : null;
                 } else {
-                    return Collections.singletonList(
-                            ComponentName.unflattenFromString(legacyAssistant).getPackageName());
+                    packageName = null;
                 }
+                return CollectionUtils.singletonOrEmpty(packageName);
             }
             case RoleManager.ROLE_BROWSER: {
                 PackageManagerInternal packageManagerInternal = LocalServices.getService(
@@ -84,44 +92,36 @@
                 return CollectionUtils.singletonOrEmpty(packageName);
             }
             case RoleManager.ROLE_DIALER: {
-                String setting = Settings.Secure.getStringForUser(
-                        mContext.getContentResolver(),
+                String setting = Settings.Secure.getStringForUser(mContext.getContentResolver(),
                         Settings.Secure.DIALER_DEFAULT_APPLICATION, userId);
-                return CollectionUtils.singletonOrEmpty(!TextUtils.isEmpty(setting)
-                        ? setting
-                        : mContext.getSystemService(TelecomManager.class).getSystemDialerPackage());
+                String packageName;
+                if (!TextUtils.isEmpty(setting)) {
+                    packageName = setting;
+                } else if (mContext.getPackageManager().isDeviceUpgrading()) {
+                    // DefaultDialerManager was using the default dialer app if
+                    // Settings.Secure.DIALER_DEFAULT_APPLICATION is invalid.
+                    // TelecomManager.getSystemDialerPackage() won't work because it might not
+                    // be ready.
+                    packageName = mContext.getString(R.string.config_defaultDialer);
+                } else {
+                    packageName = null;
+                }
+                return CollectionUtils.singletonOrEmpty(packageName);
             }
             case RoleManager.ROLE_SMS: {
-                // Moved over from SmsApplication#getApplication
-                String result = Settings.Secure.getStringForUser(
-                        mContext.getContentResolver(),
+                String setting = Settings.Secure.getStringForUser(mContext.getContentResolver(),
                         Settings.Secure.SMS_DEFAULT_APPLICATION, userId);
-                // TODO: STOPSHIP: Remove the following code once we read the value of
-                //  config_defaultSms in RoleControllerService.
-                if (result == null) {
-                    Collection<SmsApplication.SmsApplicationData> applications =
-                            SmsApplication.getApplicationCollectionAsUser(mContext, userId);
-                    SmsApplication.SmsApplicationData applicationData;
-                    String defaultPackage = mContext.getResources()
-                            .getString(com.android.internal.R.string.default_sms_application);
-                    applicationData =
-                            SmsApplication.getApplicationForPackage(applications, defaultPackage);
-
-                    if (applicationData == null) {
-                        // Are there any applications?
-                        if (applications.size() != 0) {
-                            applicationData =
-                                    (SmsApplication.SmsApplicationData) applications.toArray()[0];
-                        }
-                    }
-                    if (DEBUG) {
-                        Log.i(LOG_TAG, "Found default sms app: " + applicationData
-                                + " among: " + applications + " from " + Debug.getCallers(4));
-                    }
-                    SmsApplication.SmsApplicationData app = applicationData;
-                    result = app == null ? null : app.mPackageName;
+                String packageName;
+                if (!TextUtils.isEmpty(setting)) {
+                    packageName = setting;
+                } else if (mContext.getPackageManager().isDeviceUpgrading()) {
+                    // SmsApplication was using the default SMS app if
+                    // Settings.Secure.DIALER_DEFAULT_APPLICATION is invalid.
+                    packageName = mContext.getString(R.string.config_defaultSms);
+                } else {
+                    packageName = null;
                 }
-                return CollectionUtils.singletonOrEmpty(result);
+                return CollectionUtils.singletonOrEmpty(packageName);
             }
             case RoleManager.ROLE_HOME: {
                 PackageManager packageManager = mContext.getPackageManager();
diff --git a/services/tests/uiservicestests/src/com/android/server/notification/PreferencesHelperTest.java b/services/tests/uiservicestests/src/com/android/server/notification/PreferencesHelperTest.java
index 8f8b746..365cd80 100644
--- a/services/tests/uiservicestests/src/com/android/server/notification/PreferencesHelperTest.java
+++ b/services/tests/uiservicestests/src/com/android/server/notification/PreferencesHelperTest.java
@@ -22,6 +22,8 @@
 import static android.app.NotificationManager.IMPORTANCE_NONE;
 import static android.app.NotificationManager.IMPORTANCE_UNSPECIFIED;
 
+import static com.android.server.notification.PreferencesHelper.NOTIFICATION_CHANNEL_COUNT_LIMIT;
+
 import static junit.framework.Assert.assertNull;
 import static junit.framework.Assert.fail;
 
@@ -2690,4 +2692,51 @@
         assertFalse(mHelper.areBubblesAllowed(PKG_O, UID_O));
         verify(mHandler, times(1)).requestSort();
     }
+
+    @Test
+    public void testTooManyChannels() {
+        for (int i = 0; i < NOTIFICATION_CHANNEL_COUNT_LIMIT; i++) {
+            NotificationChannel channel = new NotificationChannel(String.valueOf(i),
+                    String.valueOf(i), NotificationManager.IMPORTANCE_HIGH);
+            mHelper.createNotificationChannel(PKG_O, UID_O, channel, true, true);
+        }
+        try {
+            NotificationChannel channel = new NotificationChannel(
+                    String.valueOf(NOTIFICATION_CHANNEL_COUNT_LIMIT),
+                    String.valueOf(NOTIFICATION_CHANNEL_COUNT_LIMIT),
+                    NotificationManager.IMPORTANCE_HIGH);
+            mHelper.createNotificationChannel(PKG_O, UID_O, channel, true, true);
+            fail("Allowed to create too many notification channels");
+        } catch (IllegalStateException e) {
+            // great
+        }
+    }
+
+    @Test
+    public void testTooManyChannels_xml() throws Exception {
+        String extraChannel = "EXTRA";
+        String extraChannel1 = "EXTRA1";
+
+        // create first... many... directly so we don't need a big xml blob in this test
+        for (int i = 0; i < NOTIFICATION_CHANNEL_COUNT_LIMIT; i++) {
+            NotificationChannel channel = new NotificationChannel(String.valueOf(i),
+                    String.valueOf(i), NotificationManager.IMPORTANCE_HIGH);
+            mHelper.createNotificationChannel(PKG_O, UID_O, channel, true, true);
+        }
+
+        final String xml = "<ranking version=\"1\">\n"
+                + "<package name=\"" + PKG_O + "\" uid=\"" + UID_O + "\" >\n"
+                + "<channel id=\"" + extraChannel + "\" name=\"hi\" importance=\"3\"/>"
+                + "<channel id=\"" + extraChannel1 + "\" name=\"hi\" importance=\"3\"/>"
+                + "</package>"
+                + "</ranking>";
+        XmlPullParser parser = Xml.newPullParser();
+        parser.setInput(new BufferedInputStream(new ByteArrayInputStream(xml.getBytes())),
+                null);
+        parser.nextTag();
+        mHelper.readXml(parser, false, UserHandle.USER_ALL);
+
+        assertNull(mHelper.getNotificationChannel(PKG_O, UID_O, extraChannel, true));
+        assertNull(mHelper.getNotificationChannel(PKG_O, UID_O, extraChannel1, true));
+    }
 }
diff --git a/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionManagerService.java b/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionManagerService.java
index e1ffb0f..46d7509 100644
--- a/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionManagerService.java
+++ b/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionManagerService.java
@@ -1281,9 +1281,12 @@
 
             RoleObserver(@NonNull @CallbackExecutor Executor executor) {
                 mRm.addOnRoleHoldersChangedListenerAsUser(executor, this, UserHandle.ALL);
-                UserHandle currentUser = UserHandle.of(LocalServices.getService(
-                        ActivityManagerInternal.class).getCurrentUserId());
-                onRoleHoldersChanged(RoleManager.ROLE_ASSISTANT, currentUser);
+                // Sync only if assistant role has been initialized.
+                if (mRm.isRoleAvailable(RoleManager.ROLE_ASSISTANT)) {
+                    UserHandle currentUser = UserHandle.of(LocalServices.getService(
+                            ActivityManagerInternal.class).getCurrentUserId());
+                    onRoleHoldersChanged(RoleManager.ROLE_ASSISTANT, currentUser);
+                }
             }
 
             private @NonNull String getDefaultRecognizer(@NonNull UserHandle user) {
diff --git a/telephony/java/android/provider/Telephony.java b/telephony/java/android/provider/Telephony.java
index 8e56fe7..38c81d3 100644
--- a/telephony/java/android/provider/Telephony.java
+++ b/telephony/java/android/provider/Telephony.java
@@ -4049,6 +4049,53 @@
         public static final String DEFAULT_SORT_ORDER = DELIVERY_TIME + " DESC";
 
         /**
+         * The Epoch Unix timestamp when the device received the message.
+         * <P>Type: INTEGER</P>
+         */
+        public static final String RECEIVED_TIME = "received_time";
+
+        /**
+         * Indicates that whether the message has been broadcasted to the application.
+         * <P>Type: BOOLEAN</P>
+         */
+        public static final String MESSAGE_BROADCASTED = "message_broadcasted";
+
+        /**
+         * The Warning Area Coordinates Elements. This element is used for geo-fencing purpose.
+         *
+         * The geometry and its coordinates are separated vertical bar, the first item is the
+         * geometry type and the remaining items are the parameter of this geometry.
+         *
+         * Only circle and polygon are supported. The coordinates are represented in Horizontal
+         * coordinates format.
+         *
+         * Coordinate encoding:
+         * "latitude, longitude"
+         * where -90.00000 <= latitude <= 90.00000 and -180.00000 <= longitude <= 180.00000
+         *
+         * Polygon encoding:
+         * "polygon|lat1,lng1|lat2,lng2|...|latn,lngn"
+         * lat1,lng1 ... latn,lngn are the vertices coordinate of the polygon.
+         *
+         * Circle encoding:
+         * "circle|lat,lng|radius".
+         * lat,lng is the center of the circle. The unit of circle's radius is meter.
+         *
+         * Example:
+         * "circle|0,0|100" mean a circle which center located at (0,0) and its radius is 100 meter.
+         * "polygon|0,1.5|0,1|1,1|1,0" mean a polygon has vertices (0,1.5),(0,1),(1,1),(1,0).
+         *
+         * There could be more than one geometry store in this field, they are separated by a
+         * semicolon.
+         *
+         * Example:
+         * "circle|0,0|100;polygon|0,0|0,1.5|1,1|1,0;circle|100.123,100|200.123"
+         *
+         * <P>Type: TEXT</P>
+         */
+        public static final String GEOMETRIES = "geometries";
+
+        /**
          * Query columns for instantiating {@link android.telephony.CellBroadcastMessage} objects.
          */
         public static final String[] QUERY_COLUMNS = {
diff --git a/telephony/java/com/android/internal/telephony/CbGeoUtils.java b/telephony/java/com/android/internal/telephony/CbGeoUtils.java
new file mode 100644
index 0000000..c973b67
--- /dev/null
+++ b/telephony/java/com/android/internal/telephony/CbGeoUtils.java
@@ -0,0 +1,359 @@
+/*
+ * Copyright (C) 2019 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 com.android.internal.telephony;
+
+import android.annotation.NonNull;
+import android.telephony.Rlog;
+import android.text.TextUtils;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+
+/**
+ * This utils class is specifically used for geo-targeting of CellBroadcast messages.
+ * The coordinates used by this utils class are latitude and longitude, but some algorithms in this
+ * class only use them as coordinates on plane, so the calculation will be inaccurate. So don't use
+ * this class for anything other then geo-targeting of cellbroadcast messages.
+ */
+public class CbGeoUtils {
+    /** Geometric interface. */
+    public interface Geometry {
+        /**
+         * Determines if the given point {@code p} is inside the geometry.
+         * @param p point in latitude, longitude format.
+         * @return {@code True} if the given point is inside the geometry.
+         */
+        boolean contains(LatLng p);
+    }
+
+    /**
+     * Tolerance for determining if the value is 0. If the absolute value of a value is less than
+     * this tolerance, it will be treated as 0.
+     */
+    public static final double EPS = 1e-7;
+
+    /** The radius of earth. */
+    public static final int EARTH_RADIUS_METER = 6371 * 1000;
+
+    private static final String TAG = "CbGeoUtils";
+
+    /** The identifier of geometry in the encoded string. */
+    private static final String CIRCLE_SYMBOL = "circle";
+    private static final String POLYGON_SYMBOL = "polygon";
+
+    /** Point represent by (latitude, longitude). */
+    public static class LatLng {
+        public final double lat;
+        public final double lng;
+
+        /**
+         * Constructor.
+         * @param lat latitude, range [-90, 90]
+         * @param lng longitude, range [-180, 180]
+         */
+        public LatLng(double lat, double lng) {
+            this.lat = lat;
+            this.lng = lng;
+        }
+
+        /**
+         * @param p the point use to calculate the subtraction result.
+         * @return the result of this point subtract the given point {@code p}.
+         */
+        public LatLng subtract(LatLng p) {
+            return new LatLng(lat - p.lat, lng - p.lng);
+        }
+
+        /**
+         * Calculate the distance in meter between this point and the given point {@code p}.
+         * @param p the point use to calculate the distance.
+         * @return the distance in meter.
+         */
+        public double distance(LatLng p) {
+            double dlat = Math.sin(0.5 * Math.toRadians(lat - p.lat));
+            double dlng = Math.sin(0.5 * Math.toRadians(lng - p.lng));
+            double x = dlat * dlat
+                    + dlng * dlng * Math.cos(Math.toRadians(lat)) * Math.cos(Math.toRadians(p.lat));
+            return 2 * Math.atan2(Math.sqrt(x), Math.sqrt(1 - x)) * EARTH_RADIUS_METER;
+        }
+    }
+
+    /**
+     * The class represents a simple polygon with at least 3 points.
+     */
+    public static class Polygon implements Geometry {
+        /**
+         * In order to reduce the loss of precision in floating point calculations, all vertices
+         * of the polygon are scaled. Set the value of scale to 1000 can take into account the
+         * actual distance accuracy of 1 meter if the EPS is 1e-7 during the calculation.
+         */
+        private static final double SCALE = 1000.0;
+
+        private final List<LatLng> mVertices;
+        private final List<Point> mScaledVertices;
+        private final LatLng mOrigin;
+
+        /**
+         * Constructs a simple polygon from the given vertices. The adjacent two vertices are
+         * connected to form an edge of the polygon. The polygon has at least 3 vertices, and the
+         * last vertices and the first vertices must be adjacent.
+         *
+         * The longitude difference in the vertices should be less than 180 degree.
+         */
+        public Polygon(@NonNull List<LatLng> vertices) {
+            mVertices = vertices;
+
+            // Find the point with smallest longitude as the mOrigin point.
+            int idx = 0;
+            for (int i = 1; i < vertices.size(); i++) {
+                if (vertices.get(i).lng < vertices.get(idx).lng) {
+                    idx = i;
+                }
+            }
+            mOrigin = vertices.get(idx);
+
+            mScaledVertices = vertices.stream()
+                    .map(latLng -> convertAndScaleLatLng(latLng))
+                    .collect(Collectors.toList());
+        }
+
+        public List<LatLng> getVertices() {
+            return mVertices;
+        }
+
+        /**
+         * Check if the given point {@code p} is inside the polygon. This method counts the number
+         * of times the polygon winds around the point P, A.K.A "winding number". The point is
+         * outside only when this "winding number" is 0.
+         *
+         * If a point is on the edge of the polygon, it is also considered to be inside the polygon.
+         */
+        @Override
+        public boolean contains(LatLng latLng) {
+            Point p = convertAndScaleLatLng(latLng);
+
+            int n = mScaledVertices.size();
+            int windingNumber = 0;
+            for (int i = 0; i < n; i++) {
+                Point a = mScaledVertices.get(i);
+                Point b = mScaledVertices.get((i + 1) % n);
+
+                // CCW is counterclockwise
+                // CCW = ab x ap
+                // CCW > 0 -> ap is on the left side of ab
+                // CCW == 0 -> ap is on the same line of ab
+                // CCW < 0 -> ap is on the right side of ab
+                int ccw = sign(crossProduct(b.subtract(a), p.subtract(a)));
+
+                if (ccw == 0) {
+                    if (Math.min(a.x, b.x) <= p.x && p.x <= Math.max(a.x, b.x)
+                            && Math.min(a.y, b.y) <= p.y && p.y <= Math.max(a.y, b.y)) {
+                        return true;
+                    }
+                } else {
+                    if (sign(a.y - p.y) <= 0) {
+                        // upward crossing
+                        if (ccw > 0 && sign(b.y - p.y) > 0) {
+                            ++windingNumber;
+                        }
+                    } else {
+                        // downward crossing
+                        if (ccw < 0 && sign(b.y - p.y) <= 0) {
+                            --windingNumber;
+                        }
+                    }
+                }
+            }
+            return windingNumber != 0;
+        }
+
+        /**
+         * Move the given point {@code latLng} to the coordinate system with {@code mOrigin} as the
+         * origin and scale it. {@code mOrigin} is selected from the vertices of a polygon, it has
+         * the smallest longitude value among all of the polygon vertices.
+         *
+         * @param latLng the point need to be converted and scaled.
+         * @Return a {@link Point} object.
+         */
+        private Point convertAndScaleLatLng(LatLng latLng) {
+            double x = latLng.lat - mOrigin.lat;
+            double y = latLng.lng - mOrigin.lng;
+
+            // If the point is in different hemispheres(western/eastern) than the mOrigin, and the
+            // edge between them cross the 180th meridian, then its relative coordinates will be
+            // extended.
+            // For example, suppose the longitude of the mOrigin is -178, and the longitude of the
+            // point to be converted is 175, then the longitude after the conversion is -8.
+            // calculation: (-178 - 8) - (-178).
+            if (sign(mOrigin.lng) != 0 && sign(mOrigin.lng) != sign(latLng.lng)) {
+                double distCross0thMeridian = Math.abs(mOrigin.lng) + Math.abs(latLng.lng);
+                if (sign(distCross0thMeridian * 2 - 360) > 0) {
+                    y = sign(mOrigin.lng) * (360 - distCross0thMeridian);
+                }
+            }
+            return new Point(x * SCALE, y * SCALE);
+        }
+
+        private static double crossProduct(Point a, Point b) {
+            return a.x * b.y - a.y * b.x;
+        }
+
+        static final class Point {
+            public final double x;
+            public final double y;
+
+            Point(double x, double y) {
+                this.x = x;
+                this.y = y;
+            }
+
+            public Point subtract(Point p) {
+                return new Point(x - p.x, y - p.y);
+            }
+        }
+    }
+
+    /** The class represents a circle. */
+    public static class Circle implements Geometry {
+        private final LatLng mCenter;
+        private final double mRadiusMeter;
+
+        public Circle(LatLng center, double radiusMeter) {
+            this.mCenter = center;
+            this.mRadiusMeter = radiusMeter;
+        }
+
+        public LatLng getCenter() {
+            return mCenter;
+        }
+
+        public double getRadius() {
+            return mRadiusMeter;
+        }
+
+        @Override
+        public boolean contains(LatLng p) {
+            return mCenter.distance(p) <= mRadiusMeter;
+        }
+    }
+
+    /**
+     * Parse the geometries from the encoded string {@code str}. The string must follow the
+     * geometry encoding specified by {@link android.provider.Telephony.CellBroadcasts#GEOMETRIES}.
+     */
+    @NonNull
+    public static List<Geometry> parseGeometriesFromString(@NonNull String str) {
+        List<Geometry> geometries = new ArrayList<>();
+        for (String geometryStr : str.split("\\s*;\\s*")) {
+            String[] geoParameters = geometryStr.split("\\s*\\|\\s*");
+            switch (geoParameters[0]) {
+                case CIRCLE_SYMBOL:
+                    geometries.add(new Circle(parseLatLngFromString(geoParameters[1]),
+                            Double.parseDouble(geoParameters[2])));
+                    break;
+                case POLYGON_SYMBOL:
+                    List<LatLng> vertices = new ArrayList<>(geoParameters.length - 1);
+                    for (int i = 1; i < geoParameters.length; i++) {
+                        vertices.add(parseLatLngFromString(geoParameters[i]));
+                    }
+                    geometries.add(new Polygon(vertices));
+                    break;
+                default:
+                    Rlog.e(TAG, "Invalid geometry format " + geometryStr);
+            }
+        }
+        return geometries;
+    }
+
+    /**
+     * Encode a list of geometry objects to string. The encoding format is specified by
+     * {@link android.provider.Telephony.CellBroadcasts#GEOMETRIES}.
+     *
+     * @param geometries the list of geometry objects need to be encoded.
+     * @return the encoded string.
+     */
+    @NonNull
+    public static String encodeGeometriesToString(@NonNull List<Geometry> geometries) {
+        return geometries.stream()
+                .map(geometry -> encodeGeometryToString(geometry))
+                .filter(encodedStr -> !TextUtils.isEmpty(encodedStr))
+                .collect(Collectors.joining(";"));
+    }
+
+
+    /**
+     * Encode the geometry object to string. The encoding format is specified by
+     * {@link android.provider.Telephony.CellBroadcasts#GEOMETRIES}.
+     * @param geometry the geometry object need to be encoded.
+     * @return the encoded string.
+     */
+    @NonNull
+    private static String encodeGeometryToString(@NonNull Geometry geometry) {
+        StringBuilder sb = new StringBuilder();
+        if (geometry instanceof Polygon) {
+            sb.append(POLYGON_SYMBOL);
+            for (LatLng latLng : ((Polygon) geometry).getVertices()) {
+                sb.append("|");
+                sb.append(latLng.lat);
+                sb.append(",");
+                sb.append(latLng.lng);
+            }
+        } else if (geometry instanceof Circle) {
+            sb.append(CIRCLE_SYMBOL);
+            Circle circle = (Circle) geometry;
+
+            // Center
+            sb.append("|");
+            sb.append(circle.getCenter().lat);
+            sb.append(",");
+            sb.append(circle.getCenter().lng);
+
+            // Radius
+            sb.append("|");
+            sb.append(circle.getRadius());
+        } else {
+            Rlog.e(TAG, "Unsupported geometry object " + geometry);
+            return null;
+        }
+        return sb.toString();
+    }
+
+    /**
+     * Parse {@link LatLng} from {@link String}. Latitude and longitude are separated by ",".
+     * Example: "13.56,-55.447".
+     *
+     * @param str encoded lat/lng string.
+     * @Return {@link LatLng} object.
+     */
+    @NonNull
+    public static LatLng parseLatLngFromString(@NonNull String str) {
+        String[] latLng = str.split("\\s*,\\s*");
+        return new LatLng(Double.parseDouble(latLng[0]), Double.parseDouble(latLng[1]));
+    }
+
+    /**
+     * @Return the sign of the given value {@code value} with the specified tolerance. Return 1
+     * means the sign is positive, -1 means negative, 0 means the value will be treated as 0.
+     */
+    public static int sign(double value) {
+        if (value > EPS) return 1;
+        if (value < -EPS) return -1;
+        return 0;
+    }
+}