class SeqNoSet {
        static final short BIT_SET_SIZE = 1024;
        private final LongObjectHashMap<CountedBitSet> bitSets = new LongObjectHashMap<>();

        /**
         * Marks this sequence number and returns {@code true} if it is seen before.
         */
        boolean getAndSet(long value) {<FILL_FUNCTION_BODY>}
    }

            assert value >= 0;
            final long key = value / BIT_SET_SIZE;
            CountedBitSet bitset = bitSets.get(key);
            if (bitset == null) {
                bitset = new CountedBitSet(BIT_SET_SIZE);
                bitSets.put(key, bitset);
            }
            final int index = Math.toIntExact(value % BIT_SET_SIZE);
            final boolean wasOn = bitset.get(index);
            bitset.set(index);
            return wasOn;
        
<no_super_class>