io.springlets.data.jpa.repository.support

Class QueryDslRepositorySupportExt<T>

java.lang.Object

org.springframework.data.jpa.repository.support.QueryDslRepositorySupport

io.springlets.data.jpa.repository.support.QueryDslRepositorySupportExt<T>

Type Parameters:

T - the entity class to manage in the repository

public class QueryDslRepositorySupportExt<T>
extends org.springframework.data.jpa.repository.support.QueryDslRepositorySupport

Base class with additional utilities for implementing repositories using QueryDsl library.

Author:

Cèsar Ordiñana at http://www.disid.com[DISID Corporation S.L.]

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	QueryDslRepositorySupportExt.AttributeMappingBuilder Factory to create a mapping between simulated attributes and the entity real ones.

Constructor Summary

Constructors

Constructor and Description
QueryDslRepositorySupportExt(Class<T> domainClass) Creates a new QueryDslRepositorySupport instance for the given domain type.

Method Summary

Modifier and Type	Method and Description
protected com.querydsl.jpa.JPQLQuery<T>	applyGlobalSearch(GlobalSearch globalSearch, com.querydsl.jpa.JPQLQuery<T> query, com.querydsl.core.types.Path<?>... globalSearchAttributes) Adds a global contains text filter on the provided attributes.
protected com.querydsl.jpa.JPQLQuery<T>	applyGlobalSearch(String text, com.querydsl.jpa.JPQLQuery<T> query, com.querydsl.core.types.Path<?>... globalSearchAttributes) Adds a global contains text filter on the provided attributes.
protected com.querydsl.jpa.JPQLQuery<T>	applyOrderById(com.querydsl.jpa.JPQLQuery<T> query) Adds to a query an order by the entity identifier related to this repository.
protected com.querydsl.jpa.JPQLQuery<T>	applyPagination(org.springframework.data.domain.Pageable pageable, com.querydsl.jpa.JPQLQuery<T> query) Applies the given Pageable to the given JPQLQuery.
protected com.querydsl.jpa.JPQLQuery<T>	applyPagination(org.springframework.data.domain.Pageable pageable, com.querydsl.jpa.JPQLQuery<T> query, Map<String,com.querydsl.core.types.Path<?>[]> attributeMapping) Applies the given Pageable to the given JPQLQuery.
protected com.querydsl.jpa.JPQLQuery<T>	applyPagination(org.springframework.data.domain.Pageable pageable, com.querydsl.jpa.JPQLQuery<T> query, QueryDslRepositorySupportExt.AttributeMappingBuilder mapping) Applies the given Pageable to the given JPQLQuery.
protected QueryDslRepositorySupportExt.AttributeMappingBuilder	buildMapper() Creates a factory to easily build an attribute mapping to real entity attribute names.
protected com.querydsl.core.types.dsl.PathBuilder<Object>	getEntityId() Returns the path of entity identifier field
protected <M> org.springframework.data.domain.Page<M>	loadPage(com.querydsl.jpa.JPQLQuery<T> query, org.springframework.data.domain.Pageable pageable, com.querydsl.core.types.Expression<M> expression) Loads a page of data with the provided pagination criteria.

Methods inherited from class org.springframework.data.jpa.repository.support.QueryDslRepositorySupport

delete, from, from, getBuilder, getEntityManager, getQuerydsl, setEntityManager, update, validate

Methods inherited from class java.lang.Object

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

Constructor Detail

QueryDslRepositorySupportExt

public QueryDslRepositorySupportExt(Class<T> domainClass)

Creates a new QueryDslRepositorySupport instance for the given domain type.

Parameters:

domainClass - must not be null.

Method Detail

applyPagination

protected com.querydsl.jpa.JPQLQuery<T> applyPagination(org.springframework.data.domain.Pageable pageable,
                                                        com.querydsl.jpa.JPQLQuery<T> query)

Applies the given Pageable to the given JPQLQuery.

Parameters:

pageable - the ordering and paging information

query - the query to apply to

Returns:

the updated query

applyPagination

protected com.querydsl.jpa.JPQLQuery<T> applyPagination(org.springframework.data.domain.Pageable pageable,
                                                        com.querydsl.jpa.JPQLQuery<T> query,
                                                        QueryDslRepositorySupportExt.AttributeMappingBuilder mapping)

Applies the given Pageable to the given JPQLQuery. Allows to map the attributes to order as provided in the Pageable to real entity attributes. This might be used to work with projections or DTOs whose attributes don't have the same name as the entity ones. It allows to map to more than one entity attribute. As an example, if the DTO used to create the Pageable has a fullName attribute, you could map that attribute to two entity attributes: name and surname. In this case, the Pageable defines an order by a fullName attribute, but que query will order by name and surname instead.

Parameters:

pageable - the ordering and paging

query -

mapping - definition of a mapping of order attribute names to real entity ones

Returns:

the updated query

applyPagination

protected com.querydsl.jpa.JPQLQuery<T> applyPagination(org.springframework.data.domain.Pageable pageable,
                                                        com.querydsl.jpa.JPQLQuery<T> query,
                                                        Map<String,com.querydsl.core.types.Path<?>[]> attributeMapping)

Applies the given Pageable to the given JPQLQuery. Allows to map the attributes to order as provided in the Pageable to real entity attributes. This might be used to work with projections or DTOs whose attributes don't have the same name as the entity ones. It allows to map to more than one entity attribute. As an example, if the DTO used to create the Pageable has a fullName attribute, you could map that attribute to two entity attributes: name and surname. In this case, the Pageable defines an order by a fullName attribute, but que query will order by name and surname instead.

Parameters:

pageable - the ordering and paging

query -

attributeMapping - definition of a mapping of order attribute names to real entity ones

Returns:

the updated query

buildMapper

protected QueryDslRepositorySupportExt.AttributeMappingBuilder buildMapper()

Creates a factory to easily build an attribute mapping to real entity attribute names.

Returns:

the mapping factory

applyOrderById

protected com.querydsl.jpa.JPQLQuery<T> applyOrderById(com.querydsl.jpa.JPQLQuery<T> query)

Adds to a query an order by the entity identifier related to this repository. This is useful as the default last order in queries where pagination is applied, so you have always an absolute order. Otherwise, the order of the results depends on the database criteria, which might change even between pages, returning confusing results for the user.

Parameters:

query -

Returns:

the updated query

getEntityId

protected com.querydsl.core.types.dsl.PathBuilder<Object> getEntityId()

Returns the path of entity identifier field

Returns:

path of entity Identifier

applyGlobalSearch

protected com.querydsl.jpa.JPQLQuery<T> applyGlobalSearch(String text,
                                                          com.querydsl.jpa.JPQLQuery<T> query,
                                                          com.querydsl.core.types.Path<?>... globalSearchAttributes)

Adds a global contains text filter on the provided attributes. WARNING: this creates a very inefficient query. If you have many entity instances to query, use instead an indexed text search solution for better performance.

Parameters:

text - the text to look for

query -

globalSearchAttributes - the list of attributes to perform the filter on

Returns:

the updated query

applyGlobalSearch

protected com.querydsl.jpa.JPQLQuery<T> applyGlobalSearch(GlobalSearch globalSearch,
                                                          com.querydsl.jpa.JPQLQuery<T> query,
                                                          com.querydsl.core.types.Path<?>... globalSearchAttributes)

Adds a global contains text filter on the provided attributes. WARNING: this creates a very inefficient query. If you have many entity instances to query, use instead an indexed text search solution for better performance.

Parameters:

globalSearch - Contains the text to look for

query -

globalSearchAttributes - the list of attributes to perform the filter on

Returns:

the updated query

loadPage

protected <M> org.springframework.data.domain.Page<M> loadPage(com.querydsl.jpa.JPQLQuery<T> query,
                                                               org.springframework.data.domain.Pageable pageable,
                                                               com.querydsl.core.types.Expression<M> expression)

Loads a page of data with the provided pagination criteria. It allows to load full entities as well as projections. TODO: the current implementation expects the query to have already applied the paging and sorting criteria, which is not what one could expect from the method signature. Sample loading entities:

 loadPage(query, pageable, QEmployee.employee);
 

Sample with a projection:

 loadPage(query, pageable, Projections.constructor(EmployeeInfo.class,
    employee.id, employee.firstName, employee.lastName, employee.phone, employee.extension,
    employee.supervisor.id, employee.supervisor.firstName, employee.supervisor.lastName));
 

Type Parameters:

M - the data type to load, usually a JPA Entity or a projection bean

Parameters:

query - the query with the pagination and ordering criteria already applied

pageable - the already applied pagination and ordering criteria

expression - the entity or projection to build with the query data

Returns:

the loaded data page