it.unimi.di.mg4j.query.nodes
Class MultiTerm

java.lang.Object
  it.unimi.di.mg4j.query.nodes.Composite
      it.unimi.di.mg4j.query.nodes.MultiTerm

All Implemented Interfaces:

Query, Serializable

public class MultiTerm
extends Composite

A node representing a virtual term obtained by merging the occurrences of the given (possibly weighted) terms.

This node is mainly useful when performing query expansion. The QueryBuilderVisitor used to generate document iterators can decide which policy to use for setting the frequency and the name of the virtual term.

Author:

Sebastiano Vigna

See Also:

MultiTermIndexIterator, Serialized Form

Field Summary

Fields inherited from class it.unimi.di.mg4j.query.nodes.Composite

query

Constructor Summary

MultiTerm(Query... query)
Creates a new multi-term node.

Method Summary

<T> T	accept(QueryBuilderVisitor<T> visitor) Accepts a visitor.
boolean	equals(Object o)
int	hashCode()
String	toString()

Methods inherited from class it.unimi.di.mg4j.query.nodes.Composite

components, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

MultiTerm

public MultiTerm(Query... query)

Creates a new multi-term node.

Parameters:

query - a vector of nodes representing distinct terms; they must be either instances of Term, or instances of Weight containing instances of Term.

Throws:

IllegalArgumentException - if some term appears twice in query, or if the specification is not followed.

Method Detail

toString

public String toString()

Overrides:

toString in class Object

accept

public <T> T accept(QueryBuilderVisitor<T> visitor)
         throws QueryBuilderVisitorException

Description copied from interface: Query

Accepts a visitor.

Parameters:

visitor - the visitor.

Returns:

the result of the visit, or null if the visit should stop.

Throws:

QueryBuilderVisitorException

See Also:

Query

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object