Package org.hibernate.search.engine.search.projection.spi

Class ListProjectionAccumulator<F,V>

java.lang.Object

org.hibernate.search.engine.search.projection.spi.ListProjectionAccumulator<F,V>

Type Parameters:

F - The type of (unconverted) field values.

V - The type of field values after the projection converter was applied.

All Implemented Interfaces:

ProjectionAccumulator<F,V,List<F>,List<V>>

public final class ListProjectionAccumulator<F,V>
extends Object
implements ProjectionAccumulator<F,V,List<F>,List<V>>

A ProjectionAccumulator that can accumulate any number of values into a List.

Nested Class Summary

Nested classes/interfaces inherited from interface org.hibernate.search.engine.search.projection.spi.ProjectionAccumulator

ProjectionAccumulator.Provider<V,R>

Method Summary

Modifier and Type	Method	Description
List<F>	accumulate(List<F> accumulated, F value)	Folds a new value in the given accumulated container.
List<F>	createInitial()	Creates the initial accumulated container.
List<V>	finish(List<F> accumulated, ProjectionConverter<? super F,? extends V> converter, FromDocumentValueConvertContext context)	Finishes the collecting, converting the accumulated container into the final result.
static <V> ProjectionAccumulator.Provider<V,List<V>>	provider()
String	toString()

Methods inherited from class java.lang.Object

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

Method Detail

provider

public static <V> ProjectionAccumulator.Provider<V,List<V>> provider()

toString

public String toString()

Overrides:

toString in class Object

createInitial

public List<F> createInitial()

Description copied from interface: ProjectionAccumulator

Creates the initial accumulated container.

This operation should be non-blocking.

Specified by:

createInitial in interface ProjectionAccumulator<F,V,List<F>,List<V>>

Returns:

The initial accumulated container, to pass to the first call to ProjectionAccumulator.accumulate(Object, Object).

accumulate

public List<F> accumulate(List<F> accumulated,
                          F value)

Description copied from interface: ProjectionAccumulator

Folds a new value in the given accumulated container.

This operation should be non-blocking.

Specified by:

accumulate in interface ProjectionAccumulator<F,V,List<F>,List<V>>

Parameters:

accumulated - The accumulated value so far. For the first call, this is a value returned by ProjectionAccumulator.createInitial(). For the next calls, this is the value returned by the previous call to ProjectionAccumulator.accumulate(Object, Object).

value - The value to accumulate.

Returns:

The new accumulated value.

finish

public List<V> finish(List<F> accumulated,
                      ProjectionConverter<? super F,? extends V> converter,
                      FromDocumentValueConvertContext context)

Description copied from interface: ProjectionAccumulator

Finishes the collecting, converting the accumulated container into the final result.

This operation may be blocking.

Specified by:

finish in interface ProjectionAccumulator<F,V,List<F>,List<V>>

Parameters:

accumulated - The temporary storage created by ProjectionAccumulator.createInitial() and populated by successive calls to ProjectionAccumulator.accumulate(Object, Object).

converter - The projection converter (from F to V).

context - The context to be passed to the projection converter.

Returns:

The final result of the collecting.