* @param filename the name of the "file" for which a readlock is requested
*
* @see #deleteOrReleaseReadLock(String)
*/
public boolean acquireReadLock(String filename) {
FileReadLockKey readLockKey = new FileReadLockKey(indexName, filename);
Object lockValue = locksCache.withFlags(Flag.SKIP_LOCKING, Flag.SKIP_CACHE_STORE).get(readLockKey);
boolean done = false;
while (done == false) {
if (lockValue != null) {
int refCount = (Integer) lockValue;