org.apache.stanbol.entityhub.servicesapi.query

Class SimilarityConstraint

java.lang.Object

org.apache.stanbol.entityhub.servicesapi.query.Constraint

org.apache.stanbol.entityhub.servicesapi.query.SimilarityConstraint

public class SimilarityConstraint
extends Constraint

Ensure that results have fields that is contextually similar. The implementation is typically based on a cosine similarity score a normalized vector space of term frequencies - inverse document frequencies as done by the MoreLikeThis feature of Solr for instance.

This type of constraint might not be supported by all the yard implementations. If it is not supported it is just ignored.

With version 0.12.0 support for Text and Reference contexts where added. The getContextType() can be used to determine the type of the parsed context and the #getStringContext(), #getTextContext() and #getReferenceContext() methods can be used to get the typed context versions. The getContext()

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.stanbol.entityhub.servicesapi.query.Constraint

Constraint.ConstraintType

Field Summary

Fields

Modifier and Type	Field and Description
protected List<String>	additionalFields
protected String	context
protected DataTypeEnum	contextType

Constructor Summary

Constructors

Constructor and Description
SimilarityConstraint(Collection<String> context, Collection<String> languages)
SimilarityConstraint(Collection<String> context, Collection<String> languages, List<String> additionalFields)
SimilarityConstraint(Collection<String> context, DataTypeEnum contextType)
SimilarityConstraint(Collection<String> context, DataTypeEnum contextType, List<String> additionalFields)
SimilarityConstraint(String context) Deprecated. use one of the constructor explicitly parsing the DataTypeEnum or the languages (assuming DataTypeEnum.Text
SimilarityConstraint(String context, List<String> additionalFields) Deprecated. use one of the constructor explicitly parsing the DataTypeEnum or the languages (assuming DataTypeEnum.Text

Method Summary

Methods

Modifier and Type	Method and Description
List<String>	getAdditionalFields() Additional fields used for similarity calculations
String	getContext() Getter for the context
DataTypeEnum	getContextType() The type of the Context.
Collection<String>	getLanguages() The languages for the Context, or null if none are defined

Methods inherited from class org.apache.stanbol.entityhub.servicesapi.query.Constraint

getBoost, getType, setBoost, toString

Methods inherited from class java.lang.Object

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

Field Detail

context

protected final String context

contextType

protected final DataTypeEnum contextType

additionalFields

protected final List<String> additionalFields

Constructor Detail

SimilarityConstraint

public SimilarityConstraint(String context)

Deprecated. use one of the constructor explicitly parsing the DataTypeEnum or the languages (assuming DataTypeEnum.Text

Constructs a Similarity Constraint with a given context. The value is interpreted as DataTypeEnum.Text with unknown language.

Parameters:

context - the context

SimilarityConstraint

public SimilarityConstraint(String context,
                    List<String> additionalFields)

Deprecated. use one of the constructor explicitly parsing the DataTypeEnum or the languages (assuming DataTypeEnum.Text

Constructs a Similarity Constraint with a given context. The value is interpreted as DataTypeEnum.Text with unknown language.

Parameters:

context - the context

additionalFields - additional fields to include in the similarity search

SimilarityConstraint

public SimilarityConstraint(Collection<String> context,
                    Collection<String> languages)

SimilarityConstraint

public SimilarityConstraint(Collection<String> context,
                    DataTypeEnum contextType)

SimilarityConstraint

public SimilarityConstraint(Collection<String> context,
                    Collection<String> languages,
                    List<String> additionalFields)

SimilarityConstraint

public SimilarityConstraint(Collection<String> context,
                    DataTypeEnum contextType,
                    List<String> additionalFields)

Method Detail

getAdditionalFields

public List<String> getAdditionalFields()

Additional fields used for similarity calculations

Returns:

getLanguages

public Collection<String> getLanguages()

The languages for the Context, or null if none are defined

Returns:

the languages or null if none. NOTE that the returned collection may contain the null value as it represents the default language

getContext

public String getContext()

Getter for the context

Returns:

the string representation of the context

getContextType

public DataTypeEnum getContextType()

The type of the Context. Can be String, Text and Reference

Returns:

the type of the context.