Package org.springframework.data.jpa.repository.query

Class KeysetScrollDelegate

java.lang.Object

org.springframework.data.jpa.repository.query.KeysetScrollDelegate

public class KeysetScrollDelegate
extends Object

Delegate for keyset scrolling.

Since:

3.1

Author:

Mark Paluch

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	KeysetScrollDelegate.QueryStrategy<E,P>	Adapter to construct scroll queries.

Constructor Summary

Constructors

Constructor	Description
KeysetScrollDelegate()

Method Summary

Modifier and Type	Method	Description
<E, P> P	createPredicate(KeysetScrollPosition keyset, Sort sort, KeysetScrollDelegate.QueryStrategy<E,P> strategy)
static Collection<String>	getProjectionInputProperties(JpaEntityInformation<?,?> entity, Collection<String> projectionProperties, Sort sort)	Return a collection of property names required to construct a keyset selection query that include all keyset and identifier properties required to resume keyset scrolling.
protected <T> List<T>	getResultWindow(List<T> list, int limit)
protected Sort	getSortOrders(Sort sort)
static KeysetScrollDelegate	of(ScrollPosition.Direction direction)	Factory method to obtain the right KeysetScrollDelegate.
protected <T> List<T>	postProcessResults(List<T> result)

Methods inherited from class java.lang.Object

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

Constructor Details

KeysetScrollDelegate

public KeysetScrollDelegate()

Method Details

of

public static KeysetScrollDelegate of(ScrollPosition.Direction direction)

Factory method to obtain the right KeysetScrollDelegate.

Parameters:

direction - the direction of scrolling.

Returns:

a KeysetScrollDelegate matching the requested direction.

getProjectionInputProperties

public static Collection<String> getProjectionInputProperties(JpaEntityInformation<?,?> entity,
 Collection<String> projectionProperties,
 Sort sort)

Return a collection of property names required to construct a keyset selection query that include all keyset and identifier properties required to resume keyset scrolling.

Parameters:

entity - the underlying entity.

projectionProperties - projection property names.

sort - sort properties.

Returns:

a collection of property names required to construct a keyset selection query

createPredicate

@Nullable
public <E,
P> P createPredicate(KeysetScrollPosition keyset,
 Sort sort,
 KeysetScrollDelegate.QueryStrategy<E,P> strategy)

getSortOrders

protected Sort getSortOrders(Sort sort)

postProcessResults

protected <T> List<T> postProcessResults(List<T> result)

getResultWindow

protected <T> List<T> getResultWindow(List<T> list,
 int limit)