spring data 自定义接口

1 spring data jpa

虽然说spring data 提供了很多DAO 接口，但是依然可能不能满足我们日常的使用，所以，有时我们需要自定义接口方法。自定义接口方法步骤如下：

1.  创建自定义工厂类：CustomerJpaRepositoryFactoryBean， 需要继承JpaRepositoryFactoryBean

     package org.zgf.spring.data.customer;  

     import java.io.Serializable;  

     import javax.persistence.EntityManager;  

     import org.springframework.data.jpa.repository.support.JpaRepositoryFactory;
     import org.springframework.data.jpa.repository.support.JpaRepositoryFactoryBean;
     import org.springframework.data.repository.Repository;
     import org.springframework.data.repository.core.RepositoryMetadata;
     import org.springframework.data.repository.core.support.RepositoryFactorySupport;  

     /**
      *  自定义工厂
      * @author: zonggf
      * @date: 2016年1月18日-下午2:16:18
      */
     public class CustomerJpaRepositoryFactoryBean<T extends Repository<S, ID>, S, ID extends Serializable>
             extends JpaRepositoryFactoryBean<T, S, ID> {  

         @Override
         protected RepositoryFactorySupport createRepositoryFactory(
                 EntityManager entityManager) {
             return new CustomerRepositoryFactory(entityManager);
         }  

         private static class CustomerRepositoryFactory<T, I extends Serializable> extends JpaRepositoryFactory {  

             private EntityManager entityManager;  

             public CustomerRepositoryFactory(EntityManager entityManager) {
                 super(entityManager);
                 this.entityManager = entityManager;
             }  

             protected Object getTargetRepository(RepositoryMetadata metadata) {
                 return new IBaseDaoImpl<T, I>((Class<T>) metadata.getDomainType(), entityManager);
             }  

             protected Class<?> getRepositoryBaseClass(RepositoryMetadata metadata) {
                 return IBaseDao.class;
             }
         }
     }  

2. 创建自定义接口：IBaseDao， 需要继承JpaRepository

    package org.zgf.spring.data.customer;  

    import java.io.Serializable;  

    import org.springframework.data.jpa.repository.JpaRepository;
    import org.springframework.data.repository.NoRepositoryBean;  

    //必须使用该注解标明，此接口不是一个Repository Bean
    @NoRepositoryBean
    public interface IBaseDao <T, ID extends Serializable> extends JpaRepository<T, ID>{  

        //自定义接口方法
        public void sayHello(String name);  

    }  

3. 创建自定义接口实现 类：IBaseDaoImpl， 名称必须是 接口名+ Impl

     package org.zgf.spring.data.customer;  

     import java.io.Serializable;  

     import javax.persistence.EntityManager;  

     import org.springframework.data.jpa.repository.support.SimpleJpaRepository;
     import org.springframework.data.repository.NoRepositoryBean;
     //必须使用该注解标明，此接口不是一个Repository Bean
     @NoRepositoryBean
     public class IBaseDaoImpl<T, ID extends Serializable> extends SimpleJpaRepository<T, ID>
             implements IBaseDao<T, ID> {  

         private EntityManager entityManager;  

         public IBaseDaoImpl(Class<T> domainClass, EntityManager em) {
             super(domainClass, em);
             this.entityManager = em;
         }  

         @Override
         public void sayHello(String name) {
             System.out.println("entityManage:" + entityManager);
             System.out.println("hello, " + name);
         }
     }  

4. 配置文件中配置自定义工厂类：

<!-- 5. 配置 SpringData -->
<!-- 加入  jpa 的命名空间   扫描 Repository Bean 所在的 package, 自定义工厂类 -->
<jpa:repositories base-package="org.zgf.spring.data" entity-manager-factory-ref="entityManagerFactory" factory-class="org.zgf.spring.data.customer.CustomerJpaRepositoryFactoryBean"/> 

5. 测试类