diff options
Diffstat (limited to 'mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/source/hls/FullSegmentEncryptionKeyCache.java')
-rw-r--r-- | mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/source/hls/FullSegmentEncryptionKeyCache.java | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/source/hls/FullSegmentEncryptionKeyCache.java b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/source/hls/FullSegmentEncryptionKeyCache.java new file mode 100644 index 0000000000..eab538582d --- /dev/null +++ b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/source/hls/FullSegmentEncryptionKeyCache.java @@ -0,0 +1,85 @@ +/* + * 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 org.mozilla.thirdparty.com.google.android.exoplayer2.source.hls; + +import android.net.Uri; +import androidx.annotation.Nullable; +import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Assertions; +import java.util.LinkedHashMap; +import java.util.Map; + +/** + * LRU cache that holds up to {@code maxSize} full-segment-encryption keys. Which each addition, + * once the cache's size exceeds {@code maxSize}, the oldest item (according to insertion order) is + * removed. + */ +/* package */ final class FullSegmentEncryptionKeyCache { + + private final LinkedHashMap<Uri, byte[]> backingMap; + + public FullSegmentEncryptionKeyCache(int maxSize) { + backingMap = + new LinkedHashMap<Uri, byte[]>( + /* initialCapacity= */ maxSize + 1, /* loadFactor= */ 1, /* accessOrder= */ false) { + @Override + protected boolean removeEldestEntry(Map.Entry<Uri, byte[]> eldest) { + return size() > maxSize; + } + }; + } + + /** + * Returns the {@code encryptionKey} cached against this {@code uri}, or null if {@code uri} is + * null or not present in the cache. + */ + @Nullable + public byte[] get(@Nullable Uri uri) { + if (uri == null) { + return null; + } + return backingMap.get(uri); + } + + /** + * Inserts an entry into the cache. + * + * @throws NullPointerException if {@code uri} or {@code encryptionKey} are null. + */ + @Nullable + public byte[] put(Uri uri, byte[] encryptionKey) { + return backingMap.put(Assertions.checkNotNull(uri), Assertions.checkNotNull(encryptionKey)); + } + + /** + * Returns true if {@code uri} is present in the cache. + * + * @throws NullPointerException if {@code uri} is null. + */ + public boolean containsUri(Uri uri) { + return backingMap.containsKey(Assertions.checkNotNull(uri)); + } + + /** + * Removes {@code uri} from the cache. If {@code uri} was present in the cahce, this returns the + * corresponding {@code encryptionKey}, otherwise null. + * + * @throws NullPointerException if {@code uri} is null. + */ + @Nullable + public byte[] remove(Uri uri) { + return backingMap.remove(Assertions.checkNotNull(uri)); + } +} |