BloomFilter Class w/ export, import

class BloomFilter {
  constructor(size, hashCount) {
    this.size = size;
    this.hashCount = hashCount;
    this.bits = new Uint8Array(size);
  }

  add(value) {
    for (let i = 0; i < this.hashCount; i++) {
      const hash = this.hash(value, i);
      this.bits[hash] = 1;
    }
  }

  remove(value) {
    for (let i = 0; i < this.hashCount; i++) {
      const hash = this.hash(value, i);
      this.bits[hash] = 0;
    }
  }

  has(value) {
    for (let i = 0; i < this.hashCount; i++) {
      const hash = this.hash(value, i);
      if (this.bits[hash] !== 1) {
        return false;
      }
    }

    return true;
  }

  hash(value, seed) {
    let hash = 0;
    for (let i = 0; i < value.length; i++) {
      hash = (hash << 5) + hash + value.charCodeAt(i);
      hash = hash & hash; // Konvertierung in 32-Bit-Integer
      hash = Math.abs(hash);
    }

    return hash % this.size;
  }

  export() {
    return {
      size: this.size,
      hashCount: this.hashCount,
      bits: Array.from(this.bits),
    };
  }

  static import(data) {
    const bloomFilter = new BloomFilter(data.size, data.hashCount);
    bloomFilter.bits = Uint8Array.from(data.bits);
    return bloomFilter;
  }
}

// Beispiel für den Export und Import des Bloom-Filters:
const bloomFilter = new BloomFilter(100, 3);
bloomFilter.add('hello');
const exportedData = bloomFilter.export();
const importedBloomFilter = BloomFilter.import(exportedData);
console.log(importedBloomFilter.has('hello')); // gibt "true" aus