#vulnerable code 
                                @Override
    public void clear() throws CacheException {
        JedisUtil.getJedis().flushDB();
    } 
                            #location 3 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Override
    public void clear() throws CacheException {
        Objects.requireNonNull(JedisUtil.getJedis()).flushDB();
    }