org.terrier.querying.parser
Class FieldQuery

java.lang.Object
  org.terrier.querying.parser.Query
      org.terrier.querying.parser.FieldQuery

All Implemented Interfaces:

Serializable, Cloneable

public class FieldQuery
extends Query

Models a query qualified with a field.

Author:

Vassilis Plachouras, Craig Macdonald

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.terrier.querying.parser.Query

Query.ForEachQueryNode

Field Summary

Fields inherited from class org.terrier.querying.parser.Query

child, tmpSTQ

Constructor Summary

FieldQuery()
An empty default constructor

FieldQuery(Query q)
Constructs a field query from the given query.

FieldQuery(Query q, String f)
Constructs a field query from the given query and the given field.

Method Summary

Object	clone() Deep Clone this object
String	getField() Gets the field that the query term should appear.
void	getTermsOf(Class<? extends Query> c, List<Query> alist, boolean req) Returns all the query terms, in subqueries that are instances of a given class
boolean	obtainControls(Set<String> allowed, Map<String,String> controls) Checks to see if field name is a valid control name, as specified by allowed, and if so adds it to the controls table and returns true to specify that this Query object is now dead.
void	obtainQueryTerms(MatchingQueryTerms terms) Prepares the query for matching by transforming the query objects to a set of query terms.
void	obtainQueryTerms(MatchingQueryTerms terms, boolean required) Prepares the query for matching by transforming the query objects to a set of query terms.
String	parseTree() Returns the parse tree for the query as a string
void	setField(String f) Sets the value of the field.
String	toString() Returns a string representation of the query.

Methods inherited from class org.terrier.querying.parser.Query

apply, applyTermPipeline, getTerms, obtainAllOf, setChild

Methods inherited from class java.lang.Object

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

Constructor Detail

FieldQuery

public FieldQuery()

An empty default constructor

FieldQuery

public FieldQuery(Query q)

Constructs a field query from the given query.

Parameters:

q - the query that is qualified with the field operator.

FieldQuery

public FieldQuery(Query q,
                  String f)

Constructs a field query from the given query and the given field.

Parameters:

q - Query the query that is qualified with the field operator.

f - String the field in which the given query should appear in.

Method Detail

clone

public Object clone()

Deep Clone this object

Overrides:

clone in class Query

getField

public String getField()

Gets the field that the query term should appear.

Returns:

String the field that the query term should appear.

setField

public void setField(String f)

Sets the value of the field.

Parameters:

f - String the value of the field.

toString

public String toString()

Returns a string representation of the query.

Specified by:

toString in class Query

Returns:

String the string of the query.

obtainQueryTerms

public void obtainQueryTerms(MatchingQueryTerms terms)

Prepares the query for matching by transforming the query objects to a set of query terms.

Overrides:

obtainQueryTerms in class Query

Parameters:

terms - MatchingQueryTerms the object which holds the query terms and their modifiers.

obtainQueryTerms

public void obtainQueryTerms(MatchingQueryTerms terms,
                             boolean required)

Prepares the query for matching by transforming the query objects to a set of query terms.

Overrides:

obtainQueryTerms in class Query

Parameters:

terms - MatchingQueryTerms the object which holds the query terms and their modifiers.

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

obtainControls

public boolean obtainControls(Set<String> allowed,
                              Map<String,String> controls)

Checks to see if field name is a valid control name, as specified by allowed, and if so adds it to the controls table and returns true to specify that this Query object is now dead.

Overrides:

obtainControls in class Query

Parameters:

allowed - A hashset of lowercase control names that may be set by user queries.

controls - The hashtable to add the found controls to

Returns:

true if this node should now be removed, false otherwise

getTermsOf

public void getTermsOf(Class<? extends Query> c,
                       List<Query> 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.

parseTree

public String parseTree()

Description copied from class: Query

Returns the parse tree for the query as a string

Specified by:

parseTree in class Query