@Override public long remove(long key) {
        final long valueAddr = hsa.get(key);
        if (valueAddr == NULL_ADDRESS) {
            return nullValue;
        }
        final long oldValue = mem.getLong(valueAddr);
        hsa.remove(key);
        return oldValue;
    }
@Test
    public void testRemove_if_same_not_exist() {
        long key = newKey();
        long value = newValue();
        assertFalseKV(map.remove(key, value), key, value);
    }