Package org.hibernate.search.backend.elasticsearch.search.projection.impl

Class ElasticsearchConstantProjection<T>

java.lang.Object

org.hibernate.search.backend.elasticsearch.search.projection.impl.AbstractElasticsearchProjection<T>

org.hibernate.search.backend.elasticsearch.search.projection.impl.ElasticsearchConstantProjection<T>

All Implemented Interfaces:

ElasticsearchSearchProjection<T>, ElasticsearchSearchProjection.Extractor<T,T>, SearchProjection<T>

public class ElasticsearchConstantProjection<T>
extends AbstractElasticsearchProjection<T>
implements ElasticsearchSearchProjection.Extractor<T,T>

Nested Class Summary

Nested classes/interfaces inherited from class org.hibernate.search.backend.elasticsearch.search.projection.impl.AbstractElasticsearchProjection

AbstractElasticsearchProjection.AbstractBuilder<P>

Nested classes/interfaces inherited from interface org.hibernate.search.backend.elasticsearch.search.projection.impl.ElasticsearchSearchProjection

ElasticsearchSearchProjection.Extractor<E,P>

Field Summary

Fields inherited from class org.hibernate.search.backend.elasticsearch.search.projection.impl.AbstractElasticsearchProjection

indexNames

Fields inherited from interface org.hibernate.search.backend.elasticsearch.search.projection.impl.ElasticsearchSearchProjection

log

Constructor Summary

Constructors

Constructor	Description
ElasticsearchConstantProjection(ElasticsearchSearchIndexScope<?> scope, T value)

Method Summary

Modifier and Type	Method	Description
T	extract(ProjectionHitMapper<?> projectionHitMapper, com.google.gson.JsonObject hit, com.google.gson.JsonObject source, ProjectionExtractContext context)	Performs hit extraction.
ElasticsearchSearchProjection.Extractor<?,T>	request(com.google.gson.JsonObject requestBody, ProjectionRequestContext context)	Contributes to the request, making sure that the requirements for this projection are met, and creating an ElasticsearchSearchProjection.Extractor that will be able to extract the result of the projection from the Elasticsearch response.
T	transform(LoadingResult<?> loadingResult, T extractedData, ProjectionTransformContext context)	Transforms the extracted data to the actual projection result.

Methods inherited from class org.hibernate.search.backend.elasticsearch.search.projection.impl.AbstractElasticsearchProjection

indexNames

Methods inherited from class java.lang.Object

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

Constructor Details

ElasticsearchConstantProjection

public ElasticsearchConstantProjection(ElasticsearchSearchIndexScope<?> scope,
 T value)

Method Details

request

public ElasticsearchSearchProjection.Extractor<?,T> request(com.google.gson.JsonObject requestBody,
 ProjectionRequestContext context)

Description copied from interface: ElasticsearchSearchProjection

Contributes to the request, making sure that the requirements for this projection are met, and creating an ElasticsearchSearchProjection.Extractor that will be able to extract the result of the projection from the Elasticsearch response.

Specified by:

request in interface ElasticsearchSearchProjection<T>

Parameters:

requestBody - The request body.

context - An execution context for the request.

Returns:

An ElasticsearchSearchProjection.Extractor, to extract the result of the projection from the Elasticsearch response.

extract

public T extract(ProjectionHitMapper<?> projectionHitMapper,
 com.google.gson.JsonObject hit,
 com.google.gson.JsonObject source,
 ProjectionExtractContext context)

Description copied from interface: ElasticsearchSearchProjection.Extractor

Performs hit extraction.

Implementations should only perform operations relative to extracting content from the index, delaying operations that rely on the mapper until ElasticsearchSearchProjection.Extractor.transform(LoadingResult, Object, ProjectionTransformContext) is called, so that blocking mapper operations (if any) do not pollute backend threads.

Specified by:

extract in interface ElasticsearchSearchProjection.Extractor<T,T>

Parameters:

projectionHitMapper - The projection hit mapper used to transform hits to entities.

hit - The part of the response body relevant to the hit to extract.

source - The part of the source that this extractor should extract from (if relevant).

context - An execution context for the extraction.

Returns:

The element extracted from the hit. Might be a key referring to an object that will be loaded by the ProjectionHitMapper. This returned object will be passed to ElasticsearchSearchProjection.Extractor.transform(LoadingResult, Object, ProjectionTransformContext).

transform

public T transform(LoadingResult<?> loadingResult,
 T extractedData,
 ProjectionTransformContext context)

Description copied from interface: ElasticsearchSearchProjection.Extractor

Transforms the extracted data to the actual projection result.

Specified by:

transform in interface ElasticsearchSearchProjection.Extractor<T,T>

Parameters:

loadingResult - Container containing all the entities that have been loaded by the ProjectionHitMapper.

extractedData - The extracted data to transform, coming from the ElasticsearchSearchProjection.Extractor.extract(ProjectionHitMapper, JsonObject, JsonObject, ProjectionExtractContext) method.

context - An execution context for the transforming.

Returns:

The final result considered as a hit.