/** {@inheritDoc} */
@Override
public void onEntryAccessed(boolean rmv, GridCacheEntry<GridGgfsBlockKey, byte[]> entry) {
if (!rmv) {
if (!entry.isCached()) return;
if (touch(entry)) shrink();
} else {
MetaEntry meta = entry.removeMeta(META_NODE);
if (meta != null && queue.unlinkx(meta.node())) changeSize(-meta.size());
}
}
/**
* @param entry Entry to touch.
* @return {@code True} if new node has been added to queue by this call.
*/
private boolean touch(GridCacheEntry<GridGgfsBlockKey, byte[]> entry) {
byte[] val = entry.peek();
int blockSize = val != null ? val.length : 0;
MetaEntry meta = entry.meta(META_NODE);
// Entry has not been enqueued yet.
if (meta == null) {
while (true) {
Node<GridCacheEntry<GridGgfsBlockKey, byte[]>> node = queue.offerLastx(entry);
meta = new MetaEntry(node, blockSize);
if (entry.putMetaIfAbsent(META_NODE, meta) != null) {
// Was concurrently added, need to clear it from queue.
queue.unlinkx(node);
// Queue has not been changed.
return false;
} else if (node.item() != null) {
if (!entry.isCached()) {
// Was concurrently evicted, need to clear it from queue.
queue.unlinkx(node);
return false;
}
// Increment current size.
changeSize(blockSize);
return true;
}
// If node was unlinked by concurrent shrink() call, we must repeat the whole cycle.
else if (!entry.removeMeta(META_NODE, node)) return false;
}
} else {
int oldBlockSize = meta.size();
Node<GridCacheEntry<GridGgfsBlockKey, byte[]>> node = meta.node();
if (queue.unlinkx(node)) {
// Move node to tail.
Node<GridCacheEntry<GridGgfsBlockKey, byte[]>> newNode = queue.offerLastx(entry);
int delta = blockSize - oldBlockSize;
if (!entry.replaceMeta(META_NODE, meta, new MetaEntry(newNode, blockSize))) {
// Was concurrently added, need to clear it from queue.
if (queue.unlinkx(newNode)) delta -= blockSize;
}
if (delta != 0) {
changeSize(delta);
if (delta > 0)
// Total size increased, so shrinking could be needed.
return true;
}
}
}
// Entry is already in queue.
return false;
}