Package it.unimi.di.big.mg4j.query.nodes

Class MultiIndexTermExpander

java.lang.Object

it.unimi.di.big.mg4j.query.nodes.AbstractTermExpander

it.unimi.di.big.mg4j.query.nodes.MultiIndexTermExpander

All Implemented Interfaces:

QueryTransformer

public class MultiIndexTermExpander
extends AbstractTermExpander

A term expander that replaces every term or prefix with a disjunction of queries; each query is made by the same term or prefix preceded by a selection over a different index.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	MultiIndexTermExpander.ExpanderVisitor

Field Summary

Fields

Modifier and Type	Field	Description
String[]	index	The list of index names that will be used to expand the term.
int	n	A copy of the length of index.

Constructor Summary

Constructors

Constructor	Description
MultiIndexTermExpander(String... index)	Creates a new multi-index term expander.

Method Summary

Modifier and Type	Method	Description
protected Query	expand(Consecutive consecutive)
protected Query	expand(OrderedAnd orderedAnd)
Query	expand(Prefix prefix)	Expands a prefix.
Query	expand(Term term)	Expands a single term.
protected MultiIndexTermExpander.ExpanderVisitor	expanderVisitor()	Returns a new expander visitor.

Methods inherited from class it.unimi.di.big.mg4j.query.nodes.AbstractTermExpander

transform

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

index

public final String[] index

The list of index names that will be used to expand the term.

n

public final int n

A copy of the length of index.

Constructor Detail

MultiIndexTermExpander

public MultiIndexTermExpander(String... index)

Creates a new multi-index term expander.

Parameters:

index - a list of index names that will be used to expand the term.

Method Detail

expanderVisitor

protected MultiIndexTermExpander.ExpanderVisitor expanderVisitor()

Description copied from class: AbstractTermExpander

Returns a new expander visitor.

Overrides:

expanderVisitor in class AbstractTermExpander

Returns:

a visitor performing the expansion.

expand

protected Query expand(Consecutive consecutive)

expand

protected Query expand(OrderedAnd orderedAnd)

expand

public Query expand(Term term)

Description copied from class: AbstractTermExpander

Expands a single term.

Specified by:

expand in class AbstractTermExpander

Parameters:

term - a term to be expanded.

Returns:

the resulting query.

expand

public Query expand(Prefix prefix)

Description copied from class: AbstractTermExpander

Expands a prefix.

Specified by:

expand in class AbstractTermExpander

Parameters:

prefix - the prefix to be expanded.

Returns:

the resulting query.