Method ceiling

src/main/java/org/mapdb/BTreeMapJava.java:428–429

(E e)

        @Override
        public E floor(E e) { return m.floorKey(e); }
        @Override
        public E ceiling(E e) { return m.ceilingKey(e); }
        @Override
        public E higher(E e) { return m.higherKey(e); }
        @Override