#fixed code
                                public void initiate() {
        ReadLastConfirmedOp rlcop = new ReadLastConfirmedOp(lh,
                new ReadLastConfirmedOp.LastConfirmedDataCallback() {
                public void readLastConfirmedDataComplete(int rc, RecoveryData data) {
                    if (rc == BKException.Code.OK) {
                        lh.lastAddPushed = lh.lastAddConfirmed = data.lastAddConfirmed;
                        lh.length = data.length;
                        doRecoveryRead();
                    } else {
                        cb.operationComplete(BKException.Code.ReadException, null);
                    }
                }
                });

        /**
         * Enable fencing on this op. When the read request reaches the bookies
         * server it will fence off the ledger, stopping any subsequent operation
         * from writing to it.
         */
        rlcop.initiateWithFencing();
    }
#vulnerable code 
                                public void initiate() {
        /** 
         * Enable fencing on this op. When the read request reaches the bookies
         * server it will fence off the ledger, stopping any subsequent operation
         * from writing to it.
         */
        int flags = BookieProtocol.FLAG_DO_FENCING;
        for (int i = 0; i < lh.metadata.currentEnsemble.size(); i++) {
            lh.bk.bookieClient.readEntry(lh.metadata.currentEnsemble.get(i), lh.ledgerId, 
                                         BookieProtocol.LAST_ADD_CONFIRMED, this, i, flags);
        }
    } 
                            #location 9 
                            #vulnerability type THREAD_SAFETY_VIOLATION