1/* 2 * Copyright (C) 2015 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 17package com.android.tv.common; 18 19import android.media.tv.TvContentRating; 20import android.support.annotation.Nullable; 21import android.support.annotation.VisibleForTesting; 22import android.text.TextUtils; 23import android.util.ArrayMap; 24import android.util.Log; 25 26import java.util.ArrayList; 27import java.util.Collections; 28import java.util.List; 29import java.util.Map; 30import java.util.Set; 31import java.util.SortedSet; 32import java.util.TreeSet; 33 34/** 35 * TvContentRating cache. 36 */ 37public final class TvContentRatingCache implements MemoryManageable { 38 private final static String TAG = "TvContentRatings"; 39 40 private final static TvContentRatingCache INSTANCE = new TvContentRatingCache(); 41 42 public final static TvContentRatingCache getInstance() { 43 return INSTANCE; 44 } 45 46 private final Map<String, TvContentRating[]> mRatingsMultiMap = new ArrayMap<>(); 47 48 /** 49 * Returns an array TvContentRatings from a string of comma separated set of rating strings 50 * creating each from {@link TvContentRating#unflattenFromString(String)} if needed. 51 * Returns {@code null} if the string is empty or contains no valid ratings. 52 */ 53 @Nullable 54 public TvContentRating[] getRatings(String commaSeparatedRatings) { 55 if (TextUtils.isEmpty(commaSeparatedRatings)) { 56 return null; 57 } 58 TvContentRating[] tvContentRatings; 59 if (mRatingsMultiMap.containsKey(commaSeparatedRatings)) { 60 tvContentRatings = mRatingsMultiMap.get(commaSeparatedRatings); 61 } else { 62 String normalizedRatings = TextUtils 63 .join(",", getSortedSetFromCsv(commaSeparatedRatings)); 64 if (mRatingsMultiMap.containsKey(normalizedRatings)) { 65 tvContentRatings = mRatingsMultiMap.get(normalizedRatings); 66 } else { 67 tvContentRatings = stringToContentRatings(commaSeparatedRatings); 68 mRatingsMultiMap.put(normalizedRatings, tvContentRatings); 69 } 70 if (!normalizedRatings.equals(commaSeparatedRatings)) { 71 // Add an entry so the non normalized entry points to the same result; 72 mRatingsMultiMap.put(commaSeparatedRatings, tvContentRatings); 73 } 74 } 75 return tvContentRatings; 76 } 77 78 /** 79 * Returns a sorted array of TvContentRatings from a comma separated string of ratings. 80 */ 81 @VisibleForTesting 82 static TvContentRating[] stringToContentRatings(String commaSeparatedRatings) { 83 if (TextUtils.isEmpty(commaSeparatedRatings)) { 84 return null; 85 } 86 Set<String> ratingStrings = getSortedSetFromCsv(commaSeparatedRatings); 87 List<TvContentRating> contentRatings = new ArrayList<>(); 88 for (String rating : ratingStrings) { 89 try { 90 contentRatings.add(TvContentRating.unflattenFromString(rating)); 91 } catch (IllegalArgumentException e) { 92 Log.e(TAG, "Can't parse the content rating: '" + rating + "'", e); 93 } 94 } 95 return contentRatings.size() == 0 ? 96 null : contentRatings.toArray(new TvContentRating[contentRatings.size()]); 97 } 98 99 private static Set<String> getSortedSetFromCsv(String commaSeparatedRatings) { 100 String[] ratingStrings = commaSeparatedRatings.split("\\s*,\\s*"); 101 return toSortedSet(ratingStrings); 102 } 103 104 private static Set<String> toSortedSet(String[] ratingStrings) { 105 if (ratingStrings.length == 0) { 106 return Collections.EMPTY_SET; 107 } else if (ratingStrings.length == 1) { 108 return Collections.singleton(ratingStrings[0]); 109 } else { 110 // Using a TreeSet here is not very efficient, however it is good enough because: 111 // - the results are cached 112 // - in testing with multiple TISs, less than 50 entries are created 113 SortedSet<String> set = new TreeSet<>(); 114 Collections.addAll(set, ratingStrings); 115 return set; 116 } 117 } 118 119 /** 120 * Returns a string of each flattened content rating, sorted and concatenated together 121 * with a comma. 122 */ 123 public static String contentRatingsToString(TvContentRating[] contentRatings) { 124 if (contentRatings == null || contentRatings.length == 0) { 125 return null; 126 } 127 String[] ratingStrings = new String[contentRatings.length]; 128 for (int i = 0; i < contentRatings.length; i++) { 129 ratingStrings[i] = contentRatings[i].flattenToString(); 130 } 131 if (ratingStrings.length == 1) { 132 return ratingStrings[0]; 133 } else { 134 return TextUtils.join(",", toSortedSet(ratingStrings)); 135 } 136 } 137 138 @Override 139 public void performTrimMemory(int level) { 140 mRatingsMultiMap.clear(); 141 } 142 143 private TvContentRatingCache() { 144 } 145} 146