Package com.yahoo.vespa.indexinglanguage.expressions

Class NGramExpression

java.lang.Object

com.yahoo.vespa.objects.Selectable

com.yahoo.vespa.indexinglanguage.expressions.Expression

com.yahoo.vespa.indexinglanguage.expressions.NGramExpression

public final class NGramExpression
extends Expression

A filter which splits incoming text into n-grams.

Author:

bratseth

Constructor Summary

Constructors

Constructor	Description
NGramExpression(com.yahoo.language.Linguistics linguistics, int gramSize)	Creates an executable ngram expression

Method Summary

Modifier and Type	Method	Description
protected void	doExecute(ExecutionContext context)
boolean	equals(Object obj)
int	getGramSize()
com.yahoo.language.Linguistics	getLinguistics()
int	hashCode()
boolean	isMutating()	Returns whether this expression outputs a different value than what it gets as input.
com.yahoo.document.DataType	setInputType(com.yahoo.document.DataType inputType, TypeContext context)	Sets the input type of this and returns the resulting output type, or null if it cannot be uniquely determined.
com.yahoo.document.DataType	setOutputType(com.yahoo.document.DataType outputType, TypeContext context)	Sets the output type of this and returns the resulting input type, or null if it cannot be uniquely determined.
String	toString()

Methods inherited from class com.yahoo.vespa.indexinglanguage.expressions.Expression

convertChildren, doResolve, execute, execute, execute, execute, execute, execute, execute, execute, execute, execute, execute, execute, fromString, fromString, getInputType, getOutputType, getOutputType, leastGeneralNonNullOf, leastGeneralOf, mostGeneralOf, newInstance, requireOutputType, requiresInput, resolve, resolve, resolve, resolve, resolve, resolve, resolve, resolve, resolve, setInputType, setOutputType, setStatementOutput

Methods inherited from class com.yahoo.vespa.objects.Selectable

select, select, selectMembers

Methods inherited from class java.lang.Object

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

Constructor Details

NGramExpression

public NGramExpression(com.yahoo.language.Linguistics linguistics,
 int gramSize)

Creates an executable ngram expression

Parameters:

linguistics - the gram splitter to use, or null if this is used for representation and will not be executed

gramSize - the gram size

Method Details

isMutating

public boolean isMutating()

Description copied from class: Expression

Returns whether this expression outputs a different value than what it gets as input. Annotating a string value does not count as modifying it.

Overrides:

isMutating in class Expression

getLinguistics

public com.yahoo.language.Linguistics getLinguistics()

getGramSize

public int getGramSize()

setInputType

public com.yahoo.document.DataType setInputType(com.yahoo.document.DataType inputType,
 TypeContext context)

Description copied from class: Expression

Sets the input type of this and returns the resulting output type, or null if it cannot be uniquely determined. Subtypes may implement this by calling setInputType(inputType, requiredType, VerificationContext context).

Overrides:

setInputType in class Expression

setOutputType

public com.yahoo.document.DataType setOutputType(com.yahoo.document.DataType outputType,
 TypeContext context)

Description copied from class: Expression

Sets the output type of this and returns the resulting input type, or null if it cannot be uniquely determined. Subtypes implement this by calling setOutputType(outputType, requiredType, VerificationContext context).

Overrides:

setOutputType in class Expression

doExecute

protected void doExecute(ExecutionContext context)

Specified by:

doExecute in class Expression

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object