Port: Similarities.BM25Simlarity
Port: Similarities.DefaultSimilarity
Port: Similarities.DFRSimilarity
Port: Similarities.Distribution classes
Port: Similarities.IBSimilarity
Port: Similarities.Lambda classes
Port: Similarities.Similarity classes
Port: Similarities.Normailization classes

and PerFieldSimilarityWrapper
Port: Finished Search.Similarities