Split NetworkStackUtils to frameworks/libs/net

Split DeviceConfig and collections-related utilities to CollectionUtils
and DeviceConfigUtils in frameworks/libs/net.

Also add implementations for contains(array, value), to avoid usage of
internal non-API utils.

The original tests are based on mockito-extended, so also add to
NetworkStackTests as a dependency. This also requires setting the test
app as debuggable in its manifest.

Bug: 17454103
Test: atest NetworkStaticLibTests
Change-Id: Ie9bed66a08b7370ebe50d0a7240b788f8b31aa77

8 files changed, 590 insertions, 1 deletions

diff --git a/common/Android.bp b/common/Android.bp
index 80a35893..8943453a 100644
--- a/common/Android.bp
+++ b/common/Android.bp
@@ -143,6 +143,7 @@ filegroup {
     name: "net-utils-services-common-srcs",
     srcs: [
         "device/android/net/NetworkFactory.java",
+        "device/com/android/net/module/util/CollectionUtils.java",
     ],
     visibility: [
         "//frameworks/base/services/net",
diff --git a/common/device/com/android/net/module/util/CollectionUtils.java b/common/device/com/android/net/module/util/CollectionUtils.java
new file mode 100644
index 00000000..74f738da
--- /dev/null
+++ b/common/device/com/android/net/module/util/CollectionUtils.java
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2020 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.net.module.util;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.util.SparseArray;
+
+import java.util.Collection;
+import java.util.Objects;
+import java.util.function.Predicate;
+
+/**
+ * Utilities for {@link Collection} and arrays.
+ */
+public final class CollectionUtils {
+    private CollectionUtils() {}
+
+    /**
+     * @return True if the array is null or 0-length.
+     */
+    public static <T> boolean isEmpty(@Nullable T[] array) {
+        return array == null || array.length == 0;
+    }
+
+    /**
+     * Returns an int array from the given Integer list.
+     */
+    @NonNull
+    public static int[] toIntArray(@NonNull Collection<Integer> list) {
+        int[] array = new int[list.size()];
+        int i = 0;
+        for (Integer item : list) {
+            array[i] = item;
+            i++;
+        }
+        return array;
+    }
+
+    /**
+     * Returns a long array from the given long list.
+     */
+    @NonNull
+    public static long[] toLongArray(@NonNull Collection<Long> list) {
+        long[] array = new long[list.size()];
+        int i = 0;
+        for (Long item : list) {
+            array[i] = item;
+            i++;
+        }
+        return array;
+    }
+
+    /**
+     * @return True if there exists at least one element in the sparse array for which
+     * condition {@code predicate}
+     */
+    public static <T> boolean any(@NonNull SparseArray<T> array, @NonNull Predicate<T> predicate) {
+        for (int i = 0; i < array.size(); ++i) {
+            if (predicate.test(array.valueAt(i))) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * @return true if the array contains the specified value.
+     */
+    public static boolean contains(@Nullable int[] array, int value) {
+        if (array == null) return false;
+        for (int element : array) {
+            if (element == value) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * @return true if the array contains the specified value.
+     */
+    public static <T> boolean contains(@Nullable T[] array, @Nullable T value) {
+        if (array == null) return false;
+        for (T element : array) {
+            if (Objects.equals(element, value)) {
+                return true;
+            }
+        }
+        return false;
+    }
+}
diff --git a/common/device/com/android/net/module/util/DeviceConfigUtils.java b/common/device/com/android/net/module/util/DeviceConfigUtils.java
new file mode 100644
index 00000000..5fec0dde
--- /dev/null
+++ b/common/device/com/android/net/module/util/DeviceConfigUtils.java
@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2020 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.net.module.util;
+
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.content.res.Resources;
+import android.provider.DeviceConfig;
+import android.util.Log;
+
+import androidx.annotation.BoolRes;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+/**
+ * Utilities for modules to query {@link DeviceConfig} and flags.
+ */
+public final class DeviceConfigUtils {
+    private DeviceConfigUtils() {}
+
+    private static final String TAG = DeviceConfigUtils.class.getSimpleName();
+
+    /**
+     * Look up the value of a property for a particular namespace from {@link DeviceConfig}.
+     * @param namespace The namespace containing the property to look up.
+     * @param name The name of the property to look up.
+     * @param defaultValue The value to return if the property does not exist or has no valid value.
+     * @return the corresponding value, or defaultValue if none exists.
+     */
+    @Nullable
+    public static String getDeviceConfigProperty(@NonNull String namespace, @NonNull String name,
+            @Nullable String defaultValue) {
+        String value = DeviceConfig.getProperty(namespace, name);
+        return value != null ? value : defaultValue;
+    }
+
+    /**
+     * Look up the value of a property for a particular namespace from {@link DeviceConfig}.
+     * @param namespace The namespace containing the property to look up.
+     * @param name The name of the property to look up.
+     * @param defaultValue The value to return if the property does not exist or its value is null.
+     * @return the corresponding value, or defaultValue if none exists.
+     */
+    public static int getDeviceConfigPropertyInt(@NonNull String namespace, @NonNull String name,
+            int defaultValue) {
+        String value = getDeviceConfigProperty(namespace, name, null /* defaultValue */);
+        try {
+            return (value != null) ? Integer.parseInt(value) : defaultValue;
+        } catch (NumberFormatException e) {
+            return defaultValue;
+        }
+    }
+
+    /**
+     * Look up the value of a property for a particular namespace from {@link DeviceConfig}.
+     *
+     * Flags like timeouts should use this method and set an appropriate min/max range: if invalid
+     * values like "0" or "1" are pushed to devices, everything would timeout. The min/max range
+     * protects against this kind of breakage.
+     * @param namespace The namespace containing the property to look up.
+     * @param name The name of the property to look up.
+     * @param minimumValue The minimum value of a property.
+     * @param maximumValue The maximum value of a property.
+     * @param defaultValue The value to return if the property does not exist or its value is null.
+     * @return the corresponding value, or defaultValue if none exists or the fetched value is
+     *         not in the provided range.
+     */
+    public static int getDeviceConfigPropertyInt(@NonNull String namespace, @NonNull String name,
+            int minimumValue, int maximumValue, int defaultValue) {
+        int value = getDeviceConfigPropertyInt(namespace, name, defaultValue);
+        if (value < minimumValue || value > maximumValue) return defaultValue;
+        return value;
+    }
+
+    /**
+     * Look up the value of a property for a particular namespace from {@link DeviceConfig}.
+     * @param namespace The namespace containing the property to look up.
+     * @param name The name of the property to look up.
+     * @param defaultValue The value to return if the property does not exist or its value is null.
+     * @return the corresponding value, or defaultValue if none exists.
+     */
+    public static boolean getDeviceConfigPropertyBoolean(@NonNull String namespace,
+            @NonNull String name, boolean defaultValue) {
+        String value = getDeviceConfigProperty(namespace, name, null /* defaultValue */);
+        return (value != null) ? Boolean.parseBoolean(value) : defaultValue;
+    }
+
+    /**
+     * Check whether or not one specific experimental feature for a particular namespace from
+     * {@link DeviceConfig} is enabled by comparing module package version
+     * with current version of property. If this property version is valid, the corresponding
+     * experimental feature would be enabled, otherwise disabled.
+     *
+     * This is useful to ensure that if a module install is rolled back, flags are not left fully
+     * rolled out on a version where they have not been well tested.
+     * @param context The global context information about an app environment.
+     * @param namespace The namespace containing the property to look up.
+     * @param name The name of the property to look up.
+     * @return true if this feature is enabled, or false if disabled.
+     */
+    public static boolean isFeatureEnabled(@NonNull Context context, @NonNull String namespace,
+            @NonNull String name) {
+        return isFeatureEnabled(context, namespace, name, false /* defaultEnabled */);
+    }
+
+    /**
+     * Check whether or not one specific experimental feature for a particular namespace from
+     * {@link DeviceConfig} is enabled by comparing module package version
+     * with current version of property. If this property version is valid, the corresponding
+     * experimental feature would be enabled, otherwise disabled.
+     *
+     * This is useful to ensure that if a module install is rolled back, flags are not left fully
+     * rolled out on a version where they have not been well tested.
+     * @param context The global context information about an app environment.
+     * @param namespace The namespace containing the property to look up.
+     * @param name The name of the property to look up.
+     * @param defaultEnabled The value to return if the property does not exist or its value is
+     *                       null.
+     * @return true if this feature is enabled, or false if disabled.
+     */
+    public static boolean isFeatureEnabled(@NonNull Context context, @NonNull String namespace,
+            @NonNull String name, boolean defaultEnabled) {
+        try {
+            final int propertyVersion = getDeviceConfigPropertyInt(namespace, name,
+                    0 /* default value */);
+            final long packageVersion = context.getPackageManager().getPackageInfo(
+                    context.getPackageName(), 0).getLongVersionCode();
+            return (propertyVersion == 0 && defaultEnabled)
+                    || (propertyVersion != 0 && packageVersion >= (long) propertyVersion);
+        } catch (PackageManager.NameNotFoundException e) {
+            Log.e(TAG, "Could not find the package name", e);
+            return false;
+        }
+    }
+
+    /**
+     * Gets boolean config from resources.
+     */
+    public static boolean getResBooleanConfig(@NonNull final Context context,
+            @BoolRes int configResource, final boolean defaultValue) {
+        final Resources res = context.getResources();
+        try {
+            return res.getBoolean(configResource);
+        } catch (Resources.NotFoundException e) {
+            return defaultValue;
+        }
+    }
+}
diff --git a/common/framework/com/android/net/module/util/ConnectivityUtils.java b/common/framework/com/android/net/module/util/ConnectivityUtils.java
new file mode 100644
index 00000000..382912bf
--- /dev/null
+++ b/common/framework/com/android/net/module/util/ConnectivityUtils.java
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2020 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.net.module.util;
+
+
+import android.annotation.Nullable;
+
+import java.net.Inet6Address;
+import java.net.InetAddress;
+
+/**
+ * Various utilities used in connectivity code.
+ */
+public final class ConnectivityUtils {
+    private ConnectivityUtils() {}
+
+
+    /**
+     * Return IP address and port in a string format.
+     */
+    public static String addressAndPortToString(InetAddress address, int port) {
+        return String.format(
+                (address instanceof Inet6Address) ? "[%s]:%d" : "%s:%d",
+                        address.getHostAddress(), port);
+    }
+
+    /**
+     * Return true if the provided address is non-null and an IPv6 Unique Local Address (RFC4193).
+     */
+    public static boolean isIPv6ULA(@Nullable InetAddress addr) {
+        return addr instanceof Inet6Address
+                && ((addr.getAddress()[0] & 0xfe) == 0xfc);
+    }
+
+    /**
+     * Returns the {@code int} nearest in value to {@code value}.
+     *
+     * @param value any {@code long} value
+     * @return the same value cast to {@code int} if it is in the range of the {@code int}
+     * type, {@link Integer#MAX_VALUE} if it is too large, or {@link Integer#MIN_VALUE} if
+     * it is too small
+     */
+    public static int saturatedCast(long value) {
+        if (value > Integer.MAX_VALUE) {
+            return Integer.MAX_VALUE;
+        }
+        if (value < Integer.MIN_VALUE) {
+            return Integer.MIN_VALUE;
+        }
+        return (int) value;
+    }
+}
diff --git a/common/tests/unit/Android.bp b/common/tests/unit/Android.bp
index 537340ef..c00202e6 100644
--- a/common/tests/unit/Android.bp
+++ b/common/tests/unit/Android.bp
@@ -9,6 +9,7 @@ android_library {
     static_libs: [
         "net-utils-framework-common",
         "androidx.test.rules",
+        "mockito-target-extended-minus-junit4",
         "net-utils-device-common",
         "net-tests-utils-host-device-common",
     ],
@@ -29,6 +30,11 @@ android_test {
     static_libs: [
         "NetworkStaticLibTestsLib",
     ],
+    jni_libs: [
+        // For mockito extended
+        "libdexmakerjvmtiagent",
+        "libstaticjvmtiagent",
+    ],
     jarjar_rules: "jarjar-rules.txt",
     test_suites: ["device-tests"],
 }
diff --git a/common/tests/unit/AndroidManifest.xml b/common/tests/unit/AndroidManifest.xml
index c747c8a5..84a20a27 100644
--- a/common/tests/unit/AndroidManifest.xml
+++ b/common/tests/unit/AndroidManifest.xml
@@ -19,7 +19,7 @@
 
     <uses-permission android:name="android.permission.INTERNET" />
 
-    <application>
+    <application android:debuggable="true">
         <uses-library android:name="android.test.runner" />
     </application>
 
diff --git a/common/tests/unit/src/com/android/net/module/util/ConnectivityUtilsTest.java b/common/tests/unit/src/com/android/net/module/util/ConnectivityUtilsTest.java
new file mode 100644
index 00000000..8af01965
--- /dev/null
+++ b/common/tests/unit/src/com/android/net/module/util/ConnectivityUtilsTest.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2020 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.net.module.util;
+
+import static android.net.InetAddresses.parseNumericAddress;
+
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import static com.android.net.module.util.ConnectivityUtils.isIPv6ULA;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+/** Tests for ConnectivityUtils */
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+public class ConnectivityUtilsTest {
+    @Test
+    public void testIsIPv6ULA() {
+        assertTrue(isIPv6ULA(parseNumericAddress("fc00::")));
+        assertTrue(isIPv6ULA(parseNumericAddress("fc00::1")));
+        assertTrue(isIPv6ULA(parseNumericAddress("fc00:1234::5678")));
+        assertTrue(isIPv6ULA(parseNumericAddress("fdff:ffff:ffff:ffff:ffff:ffff:ffff:ffff")));
+
+        assertFalse(isIPv6ULA(parseNumericAddress("fe00::")));
+        assertFalse(isIPv6ULA(parseNumericAddress("2480:1248::123:456")));
+    }
+}
diff --git a/common/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java b/common/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
new file mode 100644
index 00000000..bb78854c
--- /dev/null
+++ b/common/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
@@ -0,0 +1,202 @@
+/*
+ * 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.net.module.util;
+
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.doReturn;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.mockitoSession;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Mockito.anyInt;
+import static org.mockito.Mockito.anyString;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.eq;
+
+import android.content.Context;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.PackageManager.NameNotFoundException;
+import android.content.res.Resources;
+import android.provider.DeviceConfig;
+
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.mockito.MockitoSession;
+
+
+/**
+ * Tests for DeviceConfigUtils.
+ *
+ */
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+public class DeviceConfigUtilsTest {
+    private static final String TEST_NAME_SPACE = "connectivity";
+    private static final String TEST_EXPERIMENT_FLAG = "experiment_flag";
+    private static final int TEST_FLAG_VALUE = 28;
+    private static final String TEST_FLAG_VALUE_STRING = "28";
+    private static final int TEST_DEFAULT_FLAG_VALUE = 0;
+    private static final int TEST_MAX_FLAG_VALUE = 1000;
+    private static final int TEST_MIN_FLAG_VALUE = 100;
+    private static final long TEST_PACKAGE_VERSION = 290000000;
+    private static final String TEST_PACKAGE_NAME = "test.package.name";
+    private MockitoSession mSession;
+
+    @Mock private Context mContext;
+    @Mock private PackageManager mPm;
+    @Mock private PackageInfo mPi;
+    @Mock private Resources mResources;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        mSession = mockitoSession().spyStatic(DeviceConfig.class).startMocking();
+
+        final PackageInfo pi = new PackageInfo();
+        pi.setLongVersionCode(TEST_PACKAGE_VERSION);
+
+        doReturn(mPm).when(mContext).getPackageManager();
+        doReturn(TEST_PACKAGE_NAME).when(mContext).getPackageName();
+        doReturn(pi).when(mPm).getPackageInfo(anyString(), anyInt());
+        doReturn(mResources).when(mContext).getResources();
+    }
+
+    @After
+    public void tearDown() {
+        mSession.finishMocking();
+    }
+
+    @Test
+    public void testGetDeviceConfigPropertyInt_Null() {
+        doReturn(null).when(() -> DeviceConfig.getProperty(eq(TEST_NAME_SPACE),
+                eq(TEST_EXPERIMENT_FLAG)));
+        assertEquals(TEST_DEFAULT_FLAG_VALUE, DeviceConfigUtils.getDeviceConfigPropertyInt(
+                TEST_NAME_SPACE, TEST_EXPERIMENT_FLAG,
+                TEST_DEFAULT_FLAG_VALUE /* default value */));
+    }
+
+    @Test
+    public void testGetDeviceConfigPropertyInt_NotNull() {
+        doReturn(TEST_FLAG_VALUE_STRING).when(() -> DeviceConfig.getProperty(eq(TEST_NAME_SPACE),
+                eq(TEST_EXPERIMENT_FLAG)));
+        assertEquals(TEST_FLAG_VALUE, DeviceConfigUtils.getDeviceConfigPropertyInt(
+                TEST_NAME_SPACE, TEST_EXPERIMENT_FLAG,
+                TEST_DEFAULT_FLAG_VALUE /* default value */));
+    }
+
+    @Test
+    public void testGetDeviceConfigPropertyInt_NormalValue() {
+        doReturn(TEST_FLAG_VALUE_STRING).when(() -> DeviceConfig.getProperty(eq(TEST_NAME_SPACE),
+                eq(TEST_EXPERIMENT_FLAG)));
+        assertEquals(TEST_FLAG_VALUE, DeviceConfigUtils.getDeviceConfigPropertyInt(
+                TEST_NAME_SPACE, TEST_EXPERIMENT_FLAG, 0 /* minimum value */,
+                TEST_MAX_FLAG_VALUE /* maximum value */,
+                TEST_DEFAULT_FLAG_VALUE /* default value */));
+    }
+
+    @Test
+    public void testGetDeviceConfigPropertyInt_NullValue() {
+        doReturn(null).when(() -> DeviceConfig.getProperty(
+                eq(TEST_NAME_SPACE), eq(TEST_EXPERIMENT_FLAG)));
+        assertEquals(TEST_DEFAULT_FLAG_VALUE, DeviceConfigUtils.getDeviceConfigPropertyInt(
+                TEST_NAME_SPACE, TEST_EXPERIMENT_FLAG, 0 /* minimum value */,
+                TEST_MAX_FLAG_VALUE /* maximum value */,
+                TEST_DEFAULT_FLAG_VALUE /* default value */));
+    }
+
+    @Test
+    public void testGetDeviceConfigPropertyInt_OverMaximumValue() {
+        doReturn(Integer.toString(TEST_MAX_FLAG_VALUE + 10)).when(() -> DeviceConfig.getProperty(
+                eq(TEST_NAME_SPACE), eq(TEST_EXPERIMENT_FLAG)));
+        assertEquals(TEST_DEFAULT_FLAG_VALUE, DeviceConfigUtils.getDeviceConfigPropertyInt(
+                TEST_NAME_SPACE, TEST_EXPERIMENT_FLAG, TEST_MIN_FLAG_VALUE /* minimum value */,
+                TEST_MAX_FLAG_VALUE /* maximum value */,
+                TEST_DEFAULT_FLAG_VALUE /* default value */));
+    }
+
+    @Test
+    public void testGetDeviceConfigPropertyInt_BelowMinimumValue() {
+        doReturn(Integer.toString(TEST_MIN_FLAG_VALUE - 10)).when(() -> DeviceConfig.getProperty(
+                eq(TEST_NAME_SPACE), eq(TEST_EXPERIMENT_FLAG)));
+        assertEquals(TEST_DEFAULT_FLAG_VALUE, DeviceConfigUtils.getDeviceConfigPropertyInt(
+                TEST_NAME_SPACE, TEST_EXPERIMENT_FLAG, TEST_MIN_FLAG_VALUE /* minimum value */,
+                TEST_MAX_FLAG_VALUE /* maximum value */,
+                TEST_DEFAULT_FLAG_VALUE /* default value */));
+    }
+
+    @Test
+    public void testGetDeviceConfigPropertyBoolean_Null() {
+        doReturn(null).when(() -> DeviceConfig.getProperty(eq(TEST_NAME_SPACE),
+                eq(TEST_EXPERIMENT_FLAG)));
+        assertFalse(DeviceConfigUtils.getDeviceConfigPropertyBoolean(
+                TEST_NAME_SPACE, TEST_EXPERIMENT_FLAG,
+                false /* default value */));
+    }
+
+    @Test
+    public void testGetDeviceConfigPropertyBoolean_NotNull() {
+        doReturn("true").when(() -> DeviceConfig.getProperty(eq(TEST_NAME_SPACE),
+                eq(TEST_EXPERIMENT_FLAG)));
+        assertTrue(DeviceConfigUtils.getDeviceConfigPropertyBoolean(
+                TEST_NAME_SPACE, TEST_EXPERIMENT_FLAG,
+                false /* default value */));
+    }
+
+    @Test
+    public void testFeatureIsEnabledWithExceptionsEnabled() {
+        doReturn(TEST_FLAG_VALUE_STRING).when(() -> DeviceConfig.getProperty(eq(TEST_NAME_SPACE),
+                eq(TEST_EXPERIMENT_FLAG)));
+        assertTrue(DeviceConfigUtils.isFeatureEnabled(mContext, TEST_NAME_SPACE,
+                TEST_EXPERIMENT_FLAG));
+    }
+
+    @Test
+    public void testFeatureIsNotEnabled() {
+        doReturn(null).when(() -> DeviceConfig.getProperty(eq(TEST_NAME_SPACE),
+                eq(TEST_EXPERIMENT_FLAG)));
+        assertFalse(DeviceConfigUtils.isFeatureEnabled(mContext, TEST_NAME_SPACE,
+                TEST_EXPERIMENT_FLAG));
+    }
+
+    @Test
+    public void testFeatureIsEnabledWithException() throws Exception {
+        doReturn(TEST_FLAG_VALUE_STRING).when(() -> DeviceConfig.getProperty(eq(TEST_NAME_SPACE),
+                eq(TEST_EXPERIMENT_FLAG)));
+        doThrow(NameNotFoundException.class).when(mPm).getPackageInfo(anyString(), anyInt());
+        assertFalse(DeviceConfigUtils.isFeatureEnabled(mContext, TEST_NAME_SPACE,
+                TEST_EXPERIMENT_FLAG));
+    }
+
+    @Test
+    public void testGetResBooleanConfig() {
+        final int someResId = 1234;
+        doReturn(true).when(mResources).getBoolean(someResId);
+        assertTrue(DeviceConfigUtils.getResBooleanConfig(mContext, someResId, false));
+        doReturn(false).when(mResources).getBoolean(someResId);
+        assertFalse(DeviceConfigUtils.getResBooleanConfig(mContext, someResId, false));
+        doThrow(new Resources.NotFoundException()).when(mResources).getBoolean(someResId);
+        assertFalse(DeviceConfigUtils.getResBooleanConfig(mContext, someResId, false));
+    }
+}