JPA使用方式

1.JpaRepository

创建dao层 ==ProductCategoryRepository==接口，必须实现==JpaRepository<映射对象，主键类型>== 接口

package cn.xiaochi.dao;

import cn.xiaochi.dataobject.ProductCategory;
import org.springframework.data.jpa.repository.JpaRepository;

public interface ProductCategoryRepository extends JpaRepository<ProductCategory, Integer> {

}

==CRUDRepository== 继承==Repository==

==PagingAndSortingRepository== 继承==CRUDRepository==

==JpaRepository== 继承==PagingAndSortingRepository==

意味着只需继承接口JpaRepository, 便有了以上所有接口的功能

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2.@RepositoryDefinition注解

package cn.xiaochi.dao;

import cn.xiaochi.dataobject.ProductCategory;
import org.springframework.data.repository.RepositoryDefinition;

@RepositoryDefinition(domainClass = ProductCategory.class,idClass = Integer.class)
public interface ProductCategoryRepository {

}