关于HyperLogLog去重优化

public class OptimizationHyperLogLog {
    //hyperloglog结构
    private HyperLogLog hyperLogLog;
    //初始的一个set
    private Set<Integer> set;
     
    private double rsd;
    
    //hyperloglog的桶个数，主要内存占用
    private int bucket;

    public OptimizationHyperLogLog(double rsd){
        this.rsd=rsd;
        this.bucket=1 << HyperLogLog.log2m(rsd);
        set=new HashSet<>();      
       }

   //插入一条数据
    public void offer(Object object){
        final int x = MurmurHash.hash(object);
        int currSize=set.size();
        if(hyperLogLog==null && currSize+1>bucket){ 
           //升级为hyperloglog
           hyperLogLog=new HyperLogLog(rsd);
           for(int d: set){
               hyperLogLog.offerHashed(d);
           }
           set.clear();
        }

        if(hyperLogLog!=null){
            hyperLogLog.offerHashed(x);
        }else {
            set.add(x);
        }
    }

    //获取大小
    public long cardinality() {
      if(hyperLogLog!=null) return hyperLogLog.cardinality();
      return set.size();
    }
}