Package com.yahoo.prelude.semantics.engine

Class Evaluation

java.lang.Object

com.yahoo.prelude.semantics.engine.Evaluation

public class Evaluation
extends Object

An evaluation of a query over a rule base. There is one evaluation for each evaluation of one query over one rule base.

Author:

bratseth

Constructor Summary

Constructors

Constructor	Description
Evaluation(Query query, RuleBase ruleBase)
Evaluation(Query query, RuleBase ruleBase, int traceLevel)	Creates a new evaluation

Method Summary

Modifier and Type	Method	Description
void	addItem(Item item, TermType termType)	Adds an item to the query being evaluated in a way consistent with the query type
FlattenedItem	currentItem()	Returns the current item, or null if there is no more elements
RuleEvaluation	freshRuleEvaluation()	Returns a fresh rule evaluation starting at the current position of this
NameSpace	getNameSpace(String nameSpaceName)
Query	getQuery()
int	getQuerySize()
boolean	getStemming()	Returns whether stemmed matches are allowed.
int	getTraceLevel()	The amount of context information to collect about this evaluation.
void	indentTrace()
void	insertItems(List<Item> items, CompositeItem parent, int index, TermType desiredParentType)	Inserts an item to the query being evaluated in a way consistent with the query type
void	makeParentMutable(TermItem item)	Convert The parent of this item into a mutable item.
void	next()	Advances to the next item as current item
void	previous()
void	removeItem(int position, Item item)	Removes an item, prefers the one at/close to the given position if there are multiple ones
void	removeItem(Item item)	Removes this item
void	removeItemByIdentity(Item item)	Removes this item by identity to ensure we remove the right one if there are multiple equal items
void	reset()	Resets the item iterator to point to the first item
void	resetToLast()	Resets the item iterator to point to the last item:
RuleBase	ruleBase()	Returns the rule base this evaluates over
void	setStemming(boolean stemming)	Set to true to enable stemmed matches.
void	setToLast()	Sets the item iterator to point to the last item:
void	trace(int level, String message)
void	unindentTrace()

Methods inherited from class java.lang.Object

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

Constructor Detail

Evaluation

public Evaluation(Query query,
                  RuleBase ruleBase)

Evaluation

public Evaluation(Query query,
                  RuleBase ruleBase,
                  int traceLevel)

Creates a new evaluation

Parameters:

query - the query this evaluation is for

traceLevel - the amount of tracing to do

Method Detail

ruleBase

public RuleBase ruleBase()

Returns the rule base this evaluates over

reset

public void reset()

Resets the item iterator to point to the first item

setToLast

public void setToLast()

Sets the item iterator to point to the last item:

resetToLast

public void resetToLast()

Resets the item iterator to point to the last item:

getQuery

public Query getQuery()

setStemming

public void setStemming(boolean stemming)

Set to true to enable stemmed matches. True by default

getStemming

public boolean getStemming()

Returns whether stemmed matches are allowed. True by default

getQuerySize

public int getQuerySize()

next

public void next()

Advances to the next item as current item

previous

public void previous()

currentItem

public FlattenedItem currentItem()

Returns the current item, or null if there is no more elements

freshRuleEvaluation

public RuleEvaluation freshRuleEvaluation()

Returns a fresh rule evaluation starting at the current position of this

addItem

public void addItem(Item item,
                    TermType termType)

Adds an item to the query being evaluated in a way consistent with the query type

removeItem

public void removeItem(Item item)

Removes this item

removeItemByIdentity

public void removeItemByIdentity(Item item)

Removes this item by identity to ensure we remove the right one if there are multiple equal items

removeItem

public void removeItem(int position,
                       Item item)

Removes an item, prefers the one at/close to the given position if there are multiple ones

makeParentMutable

public void makeParentMutable(TermItem item)

Convert The parent of this item into a mutable item. Note, this may change the shape of the query tree. (E.g. if the original parent is a segment phrase, and the original parent's parent is a phrase, the terms from the parent will be moved to the parent's parent.)

Parameters:

item - the item for which the parent shall be made mutable

insertItems

public void insertItems(List<Item> items,
                        CompositeItem parent,
                        int index,
                        TermType desiredParentType)

Inserts an item to the query being evaluated in a way consistent with the query type

Parameters:

items - the items to insert

parent - the parent of these items, or null to set the root

index - the index at which to insert these into the parent

desiredParentType - the desired type of the composite which contains items when this returns

trace

public void trace(int level,
                  String message)

getTraceLevel

public int getTraceLevel()

The amount of context information to collect about this evaluation. 0 (the default) means no context information, higher numbers means more context information.

indentTrace

public void indentTrace()

unindentTrace

public void unindentTrace()

getNameSpace

public NameSpace getNameSpace(String nameSpaceName)