synchronized (entityLock(ename)) { s = new Stack(); pkCache.put(ename, s); }
s = new Stack(); pkCache.put(ename, s);
    private static Stack cacheStack(String ename) {        Stack s = (Stack) pkCache.get(ename);        if (s == null) {            synchronized (entityLock(ename)) {                s = new Stack();                pkCache.put(ename, s);            }        }        return s;    }