使用springdata JPA实现分页
1.创建dao，继承JpaSpecificationExecutor和PagingAndSortingRepository。如下：
public interface CodeEntryDao extends JpaSpecificationExecutor,PagingAndSortingRepository<CodeEntry,Long>
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2.提供findAll接口，传入Specification 和Pageable 两个参数。如下：
public Page findAll( Specification spec,Pageable pageRequest);
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3.在service中调用findAll时创建Specification和Pageable,Specification是查询条件，Pageable包含pageNumber，pageSize，sort等参数。创建过程如下。
/**
* 创建分页请求.
*/
private PageRequest buildPageRequest(int pageNumber, int pagzSize, String sortType) {
Sort sort = null;
if ("auto".equals(sortType)) {
sort = new Sort(Sort.Direction.DESC, "id");
} else if ("id".equals(sortType)) {
sort = new Sort(Sort.Direction.ASC, "entryId");
}
return new PageRequest(pageNumber - 1, pagzSize, sort);
}
/**
* 创建动态查询条件组合.
*/
private Specification buildSpecification(Map<String, Object> searchParams) {
List< SearchFilter> filters = (List) SearchFilter.parse(searchParams);
Specification spec = DynamicSpecifications.bySearchFilter(filters, CodeEntry.class);
return spec;
}
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创建Specification时需要要有searchFilter和DynamicSpecifications]类支持，点击去github克隆源码
