diff options
Diffstat (limited to 'mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/upstream/cache/LeastRecentlyUsedCacheEvictor.java')
-rw-r--r-- | mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/upstream/cache/LeastRecentlyUsedCacheEvictor.java | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/upstream/cache/LeastRecentlyUsedCacheEvictor.java b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/upstream/cache/LeastRecentlyUsedCacheEvictor.java new file mode 100644 index 0000000000..56eff06b25 --- /dev/null +++ b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/upstream/cache/LeastRecentlyUsedCacheEvictor.java @@ -0,0 +1,89 @@ +/* + * Copyright (C) 2016 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.upstream.cache; + +import org.mozilla.thirdparty.com.google.android.exoplayer2.C; +import org.mozilla.thirdparty.com.google.android.exoplayer2.upstream.cache.Cache.CacheException; +import java.util.TreeSet; + +/** Evicts least recently used cache files first. */ +public final class LeastRecentlyUsedCacheEvictor implements CacheEvictor { + + private final long maxBytes; + private final TreeSet<CacheSpan> leastRecentlyUsed; + + private long currentSize; + + public LeastRecentlyUsedCacheEvictor(long maxBytes) { + this.maxBytes = maxBytes; + this.leastRecentlyUsed = new TreeSet<>(LeastRecentlyUsedCacheEvictor::compare); + } + + @Override + public boolean requiresCacheSpanTouches() { + return true; + } + + @Override + public void onCacheInitialized() { + // Do nothing. + } + + @Override + public void onStartFile(Cache cache, String key, long position, long length) { + if (length != C.LENGTH_UNSET) { + evictCache(cache, length); + } + } + + @Override + public void onSpanAdded(Cache cache, CacheSpan span) { + leastRecentlyUsed.add(span); + currentSize += span.length; + evictCache(cache, 0); + } + + @Override + public void onSpanRemoved(Cache cache, CacheSpan span) { + leastRecentlyUsed.remove(span); + currentSize -= span.length; + } + + @Override + public void onSpanTouched(Cache cache, CacheSpan oldSpan, CacheSpan newSpan) { + onSpanRemoved(cache, oldSpan); + onSpanAdded(cache, newSpan); + } + + private void evictCache(Cache cache, long requiredSpace) { + while (currentSize + requiredSpace > maxBytes && !leastRecentlyUsed.isEmpty()) { + try { + cache.removeSpan(leastRecentlyUsed.first()); + } catch (CacheException e) { + // do nothing. + } + } + } + + private static int compare(CacheSpan lhs, CacheSpan rhs) { + long lastTouchTimestampDelta = lhs.lastTouchTimestamp - rhs.lastTouchTimestamp; + if (lastTouchTimestampDelta == 0) { + // Use the standard compareTo method as a tie-break. + return lhs.compareTo(rhs); + } + return lhs.lastTouchTimestamp < rhs.lastTouchTimestamp ? -1 : 1; + } +} |