/**
* Default constructor. Specify the size of the blocks, number of blocks, and the SlabCache this
* cache will be assigned to.
*
* @param blockSize the size of each block, in bytes
* @param numBlocks the number of blocks of blockSize this cache will hold.
* @param master the SlabCache this SingleSlabCache is assigned to.
*/
public SingleSizeCache(int blockSize, int numBlocks, SlabItemActionWatcher master) {
this.blockSize = blockSize;
this.numBlocks = numBlocks;
backingStore = new Slab(blockSize, numBlocks);
this.stats = new CacheStats();
this.actionWatcher = master;
this.size = new AtomicLong(CACHE_FIXED_OVERHEAD + backingStore.heapSize());
this.timeSinceLastAccess = new AtomicLong();
// This evictionListener is called whenever the cache automatically
// evicts something.
RemovalListener<BlockCacheKey, CacheablePair> listener =
new RemovalListener<BlockCacheKey, CacheablePair>() {
@Override
public void onRemoval(RemovalNotification<BlockCacheKey, CacheablePair> notification) {
if (!notification.wasEvicted()) {
// Only process removals by eviction, not by replacement or
// explicit removal
return;
}
CacheablePair value = notification.getValue();
timeSinceLastAccess.set(System.nanoTime() - value.recentlyAccessed.get());
stats.evict();
doEviction(notification.getKey(), value);
}
};
backingMap =
CacheBuilder.newBuilder()
.maximumSize(numBlocks - 1)
.removalListener(listener)
.<BlockCacheKey, CacheablePair>build()
.asMap();
}
public long heapSize() {
return this.size.get() + backingStore.heapSize();
}
