| /* |
| * 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 android.net.util; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.provider.DeviceConfig; |
| import android.util.SparseArray; |
| |
| import java.io.FileDescriptor; |
| import java.io.IOException; |
| import java.util.List; |
| import java.util.function.Predicate; |
| |
| |
| /** |
| * Collection of utilities for the network stack. |
| */ |
| public class NetworkStackUtils { |
| |
| /** |
| * @return True if the array is null or 0-length. |
| */ |
| public static <T> boolean isEmpty(T[] array) { |
| return array == null || array.length == 0; |
| } |
| |
| /** |
| * Close a socket, ignoring any exception while closing. |
| */ |
| public static void closeSocketQuietly(FileDescriptor fd) { |
| try { |
| SocketUtils.closeSocket(fd); |
| } catch (IOException ignored) { |
| } |
| } |
| |
| /** |
| * Returns an int array from the given Integer list. |
| */ |
| public static int[] convertToIntArray(@NonNull List<Integer> list) { |
| int[] array = new int[list.size()]; |
| for (int i = 0; i < list.size(); i++) { |
| array[i] = list.get(i); |
| } |
| return array; |
| } |
| |
| /** |
| * Returns a long array from the given long list. |
| */ |
| public static long[] convertToLongArray(@NonNull List<Long> list) { |
| long[] array = new long[list.size()]; |
| for (int i = 0; i < list.size(); i++) { |
| array[i] = list.get(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(SparseArray<T> array, Predicate<T> predicate) { |
| for (int i = 0; i < array.size(); ++i) { |
| if (predicate.test(array.valueAt(i))) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * 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 non-null |
| * 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; |
| } |
| } |