Spring Data JPA 8.PagingAndSortingRepository

分手后的思念是犯贱 2022-05-21 10:16 186阅读 0赞

# PagingAndSortingRepository #

*  该接口提供了分页与排序功能 ,继承自`CrudRepository <T，ID>`
 *  方法如下:

<table> 
 <thead> 
  <tr> 
   <th>修饰符和类型</th> 
   <th>方法和描述</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>Page</td> 
   <td>findAll(Pageable pageable) 返回Page满足Pageable对象中提供的分页限制的实体。</td> 
  </tr> 
  <tr> 
   <td>Iterable</td> 
   <td>findAll(Sort sort) 返回按给定选项排序的所有实体。</td> 
  </tr> 
 </tbody> 
</table>

*  使用范例:

@Test
        public void testPagingAndSortingRepository() {
            //pageNo 从0开始
            int pageNo = 1 - 1;
            int pageSize = 4;
    // PageRequest pageable = PageRequest.of(pageNo, pageSize);
    
            //Pageable 接口通常使用的其 PageRequest 实现类. 其中封装了需要分页的信息
            //排序相关的. Sort 封装了排序的信息
            //Order 是具体针对于某一个属性进行升序还是降序.
            Sort.Order order = Sort.Order.desc("id") ;
            Sort.Order order1 = Sort.Order.asc("email") ;
            Sort sort = Sort.by(order1,order) ;
    
            PageRequest pageable = PageRequest.of(pageNo,pageSize,sort) ;
    
    
            Page<Person> page = personRepository.findAll(pageable);
            System.out.println("总的记录数:" + page.getTotalElements());
            System.out.println("当前第几页" + (page.getNumber() + 1 ));
            System.out.println("总的页数:" + page.getTotalPages());
            System.out.println("当前页的list:" + page.getContent());
            System.out.println("当前页的记录数:" + page.getNumberOfElements());
    
        }

*  详情参考:[spring-data-api][] || [官方文档][Link 1]

[spring-data-api]: https://docs.spring.io/spring-data/jpa/docs/2.0.8.RELEASE/api/
[Link 1]: https://docs.spring.io/spring-data/commons/docs/current/api/org/springframework/data/repository/PagingAndSortingRepository.html