uk.ac.gla.terrier.querying.parser
Class RequirementQuery

java.lang.Object
  uk.ac.gla.terrier.querying.parser.Query
      uk.ac.gla.terrier.querying.parser.RequirementQuery

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

public class RequirementQuery
extends Query

Models a query where the query terms have been qualified with a requirement operator, either plus, or minus.

Version:

$Revision: 1.16 $

Author:

Vassilis Plachouras & Craig Macdonald

See Also:

Serialized Form

Constructor Summary

RequirementQuery()
An empty default constructor.

Method Summary

java.lang.Object	clone() Deep copy this Query object
boolean	getRequired() Returns True if the subquery is REQUIRED to exist, or false if it REQUIRED to NOT exit.
void	getTermsOf(java.lang.Class c, java.util.ArrayList alist, boolean req) Returns all the query terms, in subqueries that are instances of a given class.
boolean	obtainControls(java.util.HashSet allowed, java.util.Hashtable controls) This object cannot contain any controls, so this method will always return false.
void	obtainQueryTerms(MatchingQueryTerms terms) Stores the terms of the query in the given structure, which is used for matching documents to the query.
void	setRequired(boolean needed) Sets whether the query is required or not.
java.lang.String	toString() Returns a string representation of the query.

Methods inherited from class uk.ac.gla.terrier.querying.parser.Query

applyTermPipeline, obtainAllOf, obtainQueryTerms, setChild

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

RequirementQuery

public RequirementQuery()

An empty default constructor.

Method Detail

clone

public java.lang.Object clone()

Description copied from class: Query

Deep copy this Query object

Overrides:

clone in class Query

setRequired

public void setRequired(boolean needed)

Sets whether the query is required or not.

Parameters:

needed - boolean indicates whether the query is required or not.

getRequired

public boolean getRequired()

Returns True if the subquery is REQUIRED to exist, or false if it REQUIRED to NOT exit.

Returns:

See above.

toString

public java.lang.String toString()

Returns a string representation of the query.

Specified by:

toString in class Query

Returns:

String a string representation of the query.

obtainQueryTerms

public void obtainQueryTerms(MatchingQueryTerms terms)

Stores the terms of the query in the given structure, which is used for matching documents to the query.

Overrides:

obtainQueryTerms in class Query

Parameters:

terms - MatchingQueryTerms the structure that holds the query terms for matching to documents.

obtainControls

public boolean obtainControls(java.util.HashSet allowed,
                              java.util.Hashtable controls)

This object cannot contain any controls, so this method will always return false.

Overrides:

obtainControls in class Query

Returns:

false

getTermsOf

public void getTermsOf(java.lang.Class c,
                       java.util.ArrayList alist,
                       boolean req)

Returns all the query terms, in subqueries that are instances of a given class.

Specified by:

getTermsOf in class Query

Parameters:

c - Class a class of queries.

alist - ArrayList the list of query terms.

req - boolean indicates whether the subqueries are required or not.