1 /* 2 * Copyright (C) 2019 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.net.shared; 18 19 import android.annotation.NonNull; 20 21 import java.lang.reflect.Array; 22 import java.util.ArrayList; 23 import java.util.Collection; 24 import java.util.function.Function; 25 26 /** 27 * Utility methods to help convert to/from stable parcelables. 28 * @hide 29 */ 30 public final class ParcelableUtil { 31 // Below methods could be implemented easily with streams, but streams are frowned upon in 32 // frameworks code. 33 34 /** 35 * Convert a list of BaseType items to an array of ParcelableType items using the specified 36 * converter function. 37 */ toParcelableArray( @onNull Collection<BaseType> base, @NonNull Function<BaseType, ParcelableType> conv, @NonNull Class<ParcelableType> parcelClass)38 public static <ParcelableType, BaseType> ParcelableType[] toParcelableArray( 39 @NonNull Collection<BaseType> base, 40 @NonNull Function<BaseType, ParcelableType> conv, 41 @NonNull Class<ParcelableType> parcelClass) { 42 final ParcelableType[] out = (ParcelableType[]) Array.newInstance(parcelClass, base.size()); 43 int i = 0; 44 for (BaseType b : base) { 45 out[i] = conv.apply(b); 46 i++; 47 } 48 return out; 49 } 50 51 /** 52 * Convert an array of ParcelableType items to a list of BaseType items using the specified 53 * converter function. 54 */ fromParcelableArray( @onNull ParcelableType[] parceled, @NonNull Function<ParcelableType, BaseType> conv)55 public static <ParcelableType, BaseType> ArrayList<BaseType> fromParcelableArray( 56 @NonNull ParcelableType[] parceled, @NonNull Function<ParcelableType, BaseType> conv) { 57 final ArrayList<BaseType> out = new ArrayList<>(parceled.length); 58 for (ParcelableType t : parceled) { 59 out.add(conv.apply(t)); 60 } 61 return out; 62 } 63 } 64