org.apache.ambari.server.api.query

Class JpaSortBuilder<T>

java.lang.Object

org.apache.ambari.server.api.query.JpaSortBuilder<T>

public class JpaSortBuilder<T>
extends Object

The JpaSortBuilder class is used to convert and Ambari SortRequest and list of SortRequestProperty into a JPA Order list. This can then be given to a CriteriaBuilder to provide sorting in the JPA layer during a query.

This classes uses the JpaPredicateVisitor for the entity being queried in order to convert the entity fields into Path expressions.

Constructor Summary

Constructors

Constructor and Description
JpaSortBuilder() Constructor.

Method Summary

Modifier and Type	Method and Description
List<javax.persistence.criteria.Order>	buildSortOrders(SortRequest sortRequest, JpaPredicateVisitor<T> visitor) Builds the list of sort orders based on the supplied request and JPA predicate visitor.

Methods inherited from class java.lang.Object

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

Constructor Detail

JpaSortBuilder

public JpaSortBuilder()

Constructor.

Method Detail

buildSortOrders

public List<javax.persistence.criteria.Order> buildSortOrders(SortRequest sortRequest,
                                                              JpaPredicateVisitor<T> visitor)

Builds the list of sort orders based on the supplied request and JPA predicate visitor.

Parameters:

sortRequest - the Ambari sort request properties to turn into a JPA sort request. If null or the SortRequestProperty list is null, an empty list is returned.

visitor - a visitor that knows how to convert the Ambari properties into SingularAttribute (not null).

Returns:

a list of sorts or an empty list if none (never null).