/**
* Purge least recently used object from the cache
*
* @return recyclable CacheEntry
*/
protected CacheEntry purgeEntry() throws IOException {
CacheEntry entry = _first;
if (entry == null) return new CacheEntry(-1, null, null, false);
if (entry._isDirty) _recman.update(entry._recid, entry._obj, entry._serializer);
removeEntry(entry);
_hash.remove(entry._recid);
entry._obj = null;
entry._serializer = null;
entry._isDirty = false;
return entry;
}
/**
* Place an object in the cache.
*
* @throws IOException
*/
protected void cachePut(long recid, Object value, Serializer serializer, boolean dirty)
throws IOException {
CacheEntry entry = _hash.get(recid);
if (entry != null) {
entry._obj = value;
entry._serializer = serializer;
touchEntry(entry);
} else {
if (_hash.size() == _max) {
// purge and recycle entry
entry = purgeEntry();
entry._recid = recid;
entry._obj = value;
entry._isDirty = dirty;
entry._serializer = serializer;
} else {
entry = new CacheEntry(recid, value, serializer, dirty);
}
addEntry(entry);
_hash.put(entry._recid, entry);
}
}
public synchronized <A> void update(long recid, A obj, Serializer<A> serializer)
throws IOException {
checkIfClosed();
if (_softCache)
synchronized (_softHash) {
// soft cache can not contain dirty objects
SoftCacheEntry e = _softHash.remove(recid);
if (e != null) {
e.clear();
}
}
CacheEntry entry = cacheGet(recid);
if (entry != null) {
// reuse existing cache entry
entry._obj = obj;
entry._serializer = serializer;
entry._isDirty = true;
} else {
cachePut(recid, obj, serializer, true);
}
}