使用分页的Spring JPA存储库中的自定义查询 [英] Custom Query in Spring JPA Repository with Pagination

问题描述

我试过用Spring Boot实现JPA Repository，它工作正常。
现在，如果我尝试在使用@Query注释扩展JpaRepository的接口中实现自定义查询，它将正常返回Bean列表（使用NamedQuery）。
现在，当我尝试为自定义方法/查询使用分页时，它不起作用。

I have tried implementing JPA Repository with Spring Boot it works fine. Now if i try to implement custom query in interface which extends JpaRepository using @Query Annotation it works fine returns List of beans.(using NamedQuery). Now when i try to use pagination for custom method/query it doesn't work.

代码：

Controller：

Controller :

@RequestMapping("/custompages/{pageNumber}")
public String getAllEmployeesUsingNamedQueryWithPaging(@PathVariable Integer pageNumber,Model model)
{
    Page<Employee> page = employeeService.getAllEmployeesUsingNamedQueryWithPaging(pageNumber);

    System.out.println("current page "+page);
    System.out.println("current page content"+page.getContent());

     int current = page.getNumber() + 1;
    int begin = Math.max(1, current - 5);
    int end = Math.min(begin + 10, page.getTotalPages());

    model.addAttribute("empList", page.getContent());
    model.addAttribute("empPages", page);
    model.addAttribute("beginIndex", begin);
    model.addAttribute("endIndex", end);
    model.addAttribute("currentIndex", current);

    return "employeeWorkbench";
}

服务

Service

@Override
public Page<Employee> getAllEmployeesUsingNamedQueryWithPaging(Integer  
pageNumber) {

    PageRequest pageRequest =
            new PageRequest(pageNumber - 1, PAGE_SIZE, 
    Sort.Direction.ASC, "id");
    return   
employeeDao.getAllEmployeesUsingNamedQueryWithPaging(pageRequest);
}

Dao

Dao

@Transactional
public interface EmployeeDao  extends JpaRepository<Employee, Long>{

@Query(name="HQL_GET_ALL_EMPLOYEE_BY_ID")//Works Fine
public List<Employee> getEmpByIdUsingNamedQuery(@Param("empId") Long
empId);     

@Query(name="HQL_GET_ALL_EMPLOYEE") //throws exception
public Page<Employee> getAllEmployeesUsingNamedQueryWithPaging(Pageable     
pageable);  
}

NamedQuery

NamedQuery

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 
3.0//EN"  
"http://hibernate.org/dtd/hibernate-mapping-3.0.dtd">

<hibernate-mapping>

<query name="HQL_GET_ALL_EMPLOYEE">from Employee</query>

<query name="HQL_GET_ALL_EMPLOYEE_BY_ID">from Employee where id = 
:empId</query>

</hibernate-mapping>

异常：java.lang.IllegalArgumentException：为$ b $指定的类型b TypedQuery [java.lang.Long]与查询返回类型
[class com.mobicule.SpringBootJPADemo.beans.Employee]不兼容

我只想为Spring JPA Repository提供自定义方法和查询提供的分页功能。
我该如何做到这一点？

I just want to have pagination functionality provided by Spring JPA Repository for custom methods and query also. How can I achieve this?

推荐答案

我不知道为什么，但由于某种原因干脆来自Entity 会导致返回id，而您需要提供select中返回的实体，如 select f from Foo f $ b

I'm not sure why, but for some reason simply doing from Entity causes the "id" to be returned, instead you need to provide the entity returned in the select, like select f from Foo f

public interface FooRepo extends PagingAndSortingRepository<Foo, Long> {

@Query( "select f from Foo f" )
Page<Foo> findAllCustom( Pageable pageable );

Page<Foo> findAllByBarBazContaining( String baz, Pageable pageable );
}

我收到同样的错误，Foo的 。我也相信你可以按照你的名字将它们引用到xml文件中。 这里是我的完整代码

I received the same error, with just from Foo. I also believe you can reference these by name to the xml file as you were. here's my full code

进一步的测试表明，来自Foo f 的也适用，我不知道为什么需要别名，也许它是JPQL规范的一部分。

further testing says that from Foo f also works, I do not know why the alias is required, perhaps it is part of the JPQL spec.

这是一个测试，显示如何进行简单的分页，按一个属性排序和按多个排序属性

Here is a test showing how to do simple paging, sorting by one property and sorting by multiple properties

@Test
public void testFindAllCustom() throws Exception {
    Page<Foo> allCustom = fooRepo.findAllCustom( pageable );

    assertThat( allCustom.getSize(), is( 2 ) );

    Page<Foo> sortByBazAsc = fooRepo.findAllCustom( new PageRequest( 0, 2, Sort.Direction.ASC, "bar.baz" ) );

    assertThat( sortByBazAsc.iterator().next().getBar().getBaz(), is( "2baz2bfoo" ) );

    Page<Foo> complexSort = fooRepo.findAllCustom( new PageRequest( 0, 2, new Sort(
            new Sort.Order( Sort.Direction.DESC, "bar.baz" ),
            new Sort.Order( Sort.Direction.ASC, "id" )
    ) ) );

    assertThat( complexSort.iterator().next().getBar().getBaz(), is( "baz1" ) );
}

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