it.unimi.di.mg4j.index.cluster
Interface LexicalClusteringStrategy

All Superinterfaces:
ClusteringStrategy, Serializable
All Known Implementing Classes:
ChainedLexicalClusteringStrategy, ContiguousLexicalStrategy

public interface LexicalClusteringStrategy
extends ClusteringStrategy

A way to associate a term with a local index out of a given set.

A LexicalCluster needs a way to retrieve, given a term, the corresponding local index.

Author:
Alessandro Arrabito, Sebastiano Vigna
See Also:
LexicalPartitioningStrategy

Method Summary
 int globalNumber(int localIndex, int localNumber)
          Returns the global term number given a local index and a local term number (optional operation).
 int localIndex(CharSequence term)
          Returns the index to which a given term is be mapped by this strategy.
 
Methods inherited from interface it.unimi.di.mg4j.index.cluster.ClusteringStrategy
numberOfLocalIndices
 

Method Detail

localIndex

int localIndex(CharSequence term)
Returns the index to which a given term is be mapped by this strategy.

Parameters:
term - a term.
Returns:
the corresponding local index, or -1 if no index contains the term.

globalNumber

int globalNumber(int localIndex,
                 int localNumber)
Returns the global term number given a local index and a local term number (optional operation).

This operation is not, in general, necessary for a LexicalCluster to work, as no action on a local index returns local numbers. It is defined here mainly for completeness and for debugging purposes (in case it is implemented).

Parameters:
localIndex - the local index.
localNumber - the local term number.
Returns:
the global term number.