1 /* 2 * Copyright (C) 2016 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 package com.android.car.hal; 17 18 import android.util.SparseIntArray; 19 20 /** 21 * Helper class that maintains bi-directional mapping between int values. 22 * 23 * <p>This class is immutable. Use {@link #create(int[])} factory method to instantiate this class. 24 */ 25 class BidirectionalSparseIntArray { 26 private final SparseIntArray mMap; 27 private final SparseIntArray mInverseMap; 28 29 /** 30 * Creates {@link BidirectionalSparseIntArray} for provided int pairs. 31 * 32 * <p> The input array should have an even number of elements. 33 */ 34 static BidirectionalSparseIntArray create(int[] keyValuePairs) { 35 int inputLength = keyValuePairs.length; 36 if (inputLength % 2 != 0) { 37 throw new IllegalArgumentException("Odd number of key-value elements"); 38 } 39 40 BidirectionalSparseIntArray biMap = new BidirectionalSparseIntArray(inputLength / 2); 41 for (int i = 0; i < keyValuePairs.length; i += 2) { 42 biMap.put(keyValuePairs[i], keyValuePairs[i + 1]); 43 } 44 return biMap; 45 } 46 47 private BidirectionalSparseIntArray(int initialCapacity) { 48 mMap = new SparseIntArray(initialCapacity); 49 mInverseMap = new SparseIntArray(initialCapacity); 50 } 51 52 private void put(int key, int value) { 53 mMap.put(key, value); 54 mInverseMap.put(value, key); 55 } 56 57 int getValue(int key, int defaultValue) { 58 return mMap.get(key, defaultValue); 59 } 60 61 int getKey(int value, int defaultKey) { 62 return mInverseMap.get(value, defaultKey); 63 } 64 } 65
