sy117 / bloom-filter-impl

Java implementation of Bloom Filter

bloom-filter-impl

Implementation of Bloom Filter in Java

Bloom Filter:

• Bloom filter is a probabilistic data structure which is used to find association of a member in a set.
• Bloom filter is space optimized because it uses bits(after hasing key) to store a key in a set.
• If Bloom filter return FALSE for association of a member in a set,that means member is not part of that set. True positive rate of bloom filter is 1.
• If Bloom filter return TRUE for association of a member in a set, that means member might be or might not be part of that set. False positive rate of bloom filter is greater than 0.
• The false positive rate depends on multiple factors like type of hash function, number of hash function, no of insertions etc..
• Guava library provides implementation of Bloom Filter in Java. Check this

Optimal number of hash functions(n):

Optimal number of bits required(m):

Correlation between Size of Bloom Filter and False Positive Rate:

Correlation between Num of Hash Functions and False Positive Rate: