probfilter

probfilter is a Java / Scala library for conflict-free replicated probabilistic filters.

Usage

To add probfilter as dependency, using Maven for instance, include the following snippet:

<dependency>
    <groupId>com.c6h5no2</groupId>
    <artifactId>probfilter-core</artifactId>
    <version>0.1.1</version>
</dependency>

If you need to work with Akka Cluster, include also the adapters:

<dependency>
    <groupId>com.c6h5no2</groupId>
    <artifactId>probfilter-akka</artifactId>
    <version>0.1.1</version>
</dependency>

Substitute version if necessary.

Data Types

probfilter provides the following filters implemented as state-based (aka convergent) CRDTs, coming with both immutable and mutable variants.

• interface CvRFilter: convergent replicated filter
  • class GBloomFilter: grow-only replicated bloom filter
  • class GCuckooFilter: grow-only replicated cuckoo filter
  • class ORCuckooFilter: observed-remove replicated cuckoo filter
  • class ScGBloomFilter: scalable grow-only replicated bloom filter
  • class ScGCuckooFilter: scalable grow-only replicated cuckoo filter
  • class ScORCuckooFilter: scalable observed-remove replicated cuckoo filter

Besides, there are also two adapter classes for convenience.

• class FluentCvRFilter: offers a fluent interface
• class ReplicatedFilter: implements Akka's ReplicatedData

Example

int elem = 42;
var filter1 = new ORCuckooFilter.Immutable<>(strategy, (short) 1).asFluent();
var filter2 = new ORCuckooFilter.Immutable<>(strategy, (short) 2).asFluent();

filter1 = filter1.add(elem);
assert filter1.contains(elem);

filter2 = filter2.merge(filter1);
assert filter2.contains(elem);

filter2 = filter2.remove(elem);
assert !filter2.contains(elem);

filter1 = filter1.merge(filter2);
assert !filter1.contains(elem);

Paper

Thesis