dragon.ir.query

Class AbstractIRQuery

java.lang.Object

dragon.ir.query.AbstractIRQuery

All Implemented Interfaces:

IRQuery

Direct Known Subclasses:

AbstractPredicate, RelBoolQuery, RelSimpleQuery

public abstract class AbstractIRQuery
extends Object
implements IRQuery

Abstract class of IR query

Copyright: Copyright (c) 2005

Company: IST, Drexel University

Version:

1.0

Author:

Davis Zhou

Field Summary

Fields

Modifier and Type	Field and Description
protected ArrayList	children
protected Operator	optr

Constructor Summary

Constructors

Constructor and Description
AbstractIRQuery()

Method Summary

Modifier and Type	Method and Description
IRQuery	getChild(int index)
int	getChildNum()
Operator	getOperator()
int	getQueryKey()
double	getSelectivity()
protected String[]	getTokenList(String query)
boolean	isCompoundQuery() If the current query denotes a simple predicate, this method returns false, otherwise true.
boolean	isPredicate() A predicate always begins with a ltter T (term predicate), R(relation predicate), or M(modifier predicate)
boolean	isRelBoolQuery()
boolean	isRelSimpleQuery()
boolean	parse(String query)
protected abstract void	parse(String[] expression)
void	setQueryKey(int key)
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

optr

protected Operator optr

children

protected ArrayList children

Constructor Detail

AbstractIRQuery

public AbstractIRQuery()

Method Detail

getQueryKey

public int getQueryKey()

Specified by:

getQueryKey in interface IRQuery

Returns:

the unique id of the query

setQueryKey

public void setQueryKey(int key)

Specified by:

setQueryKey in interface IRQuery

isPredicate

public boolean isPredicate()

Description copied from interface: IRQuery

A predicate always begins with a ltter T (term predicate), R(relation predicate), or M(modifier predicate)

Specified by:

isPredicate in interface IRQuery

Returns:

true if the the current query denotes a simple predicate, otherwise false.

isCompoundQuery

public boolean isCompoundQuery()

Description copied from interface: IRQuery

If the current query denotes a simple predicate, this method returns false, otherwise true.

Specified by:

isCompoundQuery in interface IRQuery

Returns:

false if the the current query denotes a simple predicate, otherwise true.

isRelSimpleQuery

public boolean isRelSimpleQuery()

Specified by:

isRelSimpleQuery in interface IRQuery

isRelBoolQuery

public boolean isRelBoolQuery()

Specified by:

isRelBoolQuery in interface IRQuery

parse

public boolean parse(String query)

Specified by:

parse in interface IRQuery

Parameters:

query - the query string

Returns:

a structured query

getChildNum

public int getChildNum()

Specified by:

getChildNum in interface IRQuery

getChild

public IRQuery getChild(int index)

Specified by:

getChild in interface IRQuery

getSelectivity

public double getSelectivity()

Specified by:

getSelectivity in interface IRQuery

getOperator

public Operator getOperator()

Specified by:

getOperator in interface IRQuery

toString

public String toString()

Specified by:

toString in interface IRQuery

Overrides:

toString in class Object

getTokenList

protected String[] getTokenList(String query)

parse

protected abstract void parse(String[] expression)