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 17 package com.android.tv.common; 18 19 import android.media.tv.TvContentRating; 20 import android.support.annotation.Nullable; 21 import android.support.annotation.VisibleForTesting; 22 import android.text.TextUtils; 23 import android.util.ArrayMap; 24 import android.util.Log; 25 26 import java.util.ArrayList; 27 import java.util.Collections; 28 import java.util.List; 29 import java.util.Map; 30 import java.util.Set; 31 import java.util.SortedSet; 32 import java.util.TreeSet; 33 34 /** 35 * TvContentRating cache. 36 */ 37 public final class TvContentRatingCache implements MemoryManageable { 38 private final static String TAG = "TvContentRatings"; 39 40 private final static TvContentRatingCache INSTANCE = new TvContentRatingCache(); 41 getInstance()42 public static TvContentRatingCache getInstance() { 43 return INSTANCE; 44 } 45 46 // @GuardedBy("TvContentRatingCache.this") 47 private final Map<String, TvContentRating[]> mRatingsMultiMap = new ArrayMap<>(); 48 49 /** 50 * Returns an array TvContentRatings from a string of comma separated set of rating strings 51 * creating each from {@link TvContentRating#unflattenFromString(String)} if needed. 52 * Returns {@code null} if the string is empty or contains no valid ratings. 53 */ 54 @Nullable getRatings(String commaSeparatedRatings)55 public synchronized TvContentRating[] getRatings(String commaSeparatedRatings) { 56 if (TextUtils.isEmpty(commaSeparatedRatings)) { 57 return null; 58 } 59 TvContentRating[] tvContentRatings; 60 if (mRatingsMultiMap.containsKey(commaSeparatedRatings)) { 61 tvContentRatings = mRatingsMultiMap.get(commaSeparatedRatings); 62 } else { 63 String normalizedRatings = TextUtils 64 .join(",", getSortedSetFromCsv(commaSeparatedRatings)); 65 if (mRatingsMultiMap.containsKey(normalizedRatings)) { 66 tvContentRatings = mRatingsMultiMap.get(normalizedRatings); 67 } else { 68 tvContentRatings = stringToContentRatings(commaSeparatedRatings); 69 mRatingsMultiMap.put(normalizedRatings, tvContentRatings); 70 } 71 if (!normalizedRatings.equals(commaSeparatedRatings)) { 72 // Add an entry so the non normalized entry points to the same result; 73 mRatingsMultiMap.put(commaSeparatedRatings, tvContentRatings); 74 } 75 } 76 return tvContentRatings; 77 } 78 79 /** 80 * Returns a sorted array of TvContentRatings from a comma separated string of ratings. 81 */ 82 @VisibleForTesting stringToContentRatings(String commaSeparatedRatings)83 static TvContentRating[] stringToContentRatings(String commaSeparatedRatings) { 84 if (TextUtils.isEmpty(commaSeparatedRatings)) { 85 return null; 86 } 87 Set<String> ratingStrings = getSortedSetFromCsv(commaSeparatedRatings); 88 List<TvContentRating> contentRatings = new ArrayList<>(); 89 for (String rating : ratingStrings) { 90 try { 91 contentRatings.add(TvContentRating.unflattenFromString(rating)); 92 } catch (IllegalArgumentException e) { 93 Log.e(TAG, "Can't parse the content rating: '" + rating + "'", e); 94 } 95 } 96 return contentRatings.size() == 0 ? 97 null : contentRatings.toArray(new TvContentRating[contentRatings.size()]); 98 } 99 getSortedSetFromCsv(String commaSeparatedRatings)100 private static Set<String> getSortedSetFromCsv(String commaSeparatedRatings) { 101 String[] ratingStrings = commaSeparatedRatings.split("\\s*,\\s*"); 102 return toSortedSet(ratingStrings); 103 } 104 toSortedSet(String[] ratingStrings)105 private static Set<String> toSortedSet(String[] ratingStrings) { 106 if (ratingStrings.length == 0) { 107 return Collections.EMPTY_SET; 108 } else if (ratingStrings.length == 1) { 109 return Collections.singleton(ratingStrings[0]); 110 } else { 111 // Using a TreeSet here is not very efficient, however it is good enough because: 112 // - the results are cached 113 // - in testing with multiple TISs, less than 50 entries are created 114 SortedSet<String> set = new TreeSet<>(); 115 Collections.addAll(set, ratingStrings); 116 return set; 117 } 118 } 119 120 /** 121 * Returns a string of each flattened content rating, sorted and concatenated together 122 * with a comma. 123 */ contentRatingsToString(TvContentRating[] contentRatings)124 public static String contentRatingsToString(TvContentRating[] contentRatings) { 125 if (contentRatings == null || contentRatings.length == 0) { 126 return null; 127 } 128 String[] ratingStrings = new String[contentRatings.length]; 129 for (int i = 0; i < contentRatings.length; i++) { 130 ratingStrings[i] = contentRatings[i].flattenToString(); 131 } 132 if (ratingStrings.length == 1) { 133 return ratingStrings[0]; 134 } else { 135 return TextUtils.join(",", toSortedSet(ratingStrings)); 136 } 137 } 138 139 @Override performTrimMemory(int level)140 public synchronized void performTrimMemory(int level) { 141 mRatingsMultiMap.clear(); 142 } 143 TvContentRatingCache()144 private TvContentRatingCache() { 145 } 146 } 147