Jpadao層接口

package cn.itcast.dao;

import cn.itcast.entity.Customer;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.JpaSpecificationExecutor;

/*
* 符合SpringDataJpa的dao層接口規(guī)范
* JpaRepository<操作的實(shí)體類泛型，實(shí)體類中主鍵屬性的類型>
*       *封裝了基本增刪改查操作
* JpaSpecificationExecutor<操作的實(shí)體類類型>
*       *封裝了復(fù)雜查詢(分頁)
* */

public interface CustomerDao extends JpaRepository<Customer, Long>, JpaSpecificationExecutor<Customer> {
}

測試增刪改查

package cn.itcast.test;

import cn.itcast.entity.Customer;
import cn.itcast.dao.CustomerDao;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import java.util.List;

@RunWith(SpringJUnit4ClassRunner.class)//聲明spring提供的單元測試環(huán)境
@ContextConfiguration(locations = "classpath:applicationContext.xml")//指定spring容器的配置信息
public class CustomerDaoTest {
@Autowired
    private CustomerDao customerDao;
/*
* 根據(jù)id查詢
* */
@Test
    public void testFindOne(){
    Customer one = customerDao.findOne(3l);
    System.out.println(one);
        }
        /*
        * save:保存或者更新
        *       根據(jù)傳遞對象是否存在主鍵id
        *       如果沒有主鍵id屬性，保存
        *       存在主鍵id屬性，根據(jù)id查詢數(shù)據(jù)皿曲，更新數(shù)據(jù)
        * */
        @Test
    public void testSave(){
            Customer customer = new Customer();
        customer.setCustName("小李子");
        customer.setCustLevel("vip");
        customer.setCustIndustry("it教育");
        customerDao.save(customer);
        }
    @Test
    public void testUpData(){
        Customer customer = customerDao.findOne(3l);
        customer.setCustName("劉強(qiáng)東");
        customerDao.save(customer);
    }
    /*
    *刪除用戶
    * */
    @Test
    public void testDelete(){
        customerDao.delete(6l);
    }
    /*
    *查詢所有
    **/
    @Test
    public void testFindALll(){
        List<Customer> all = customerDao.findAll();
        for (Customer customer:all){
            System.out.println(customer);
        }
    }
    /*
    * 測試統(tǒng)計(jì)查詢：查詢客戶的總數(shù)量
    * */
    @Test
    public void testCount(){
        long count = customerDao.count();
        System.out.println(count);
    }
    /*
    *測試：判斷id為3的客戶是否存在
    *       1.可以查詢以下id為3的客戶
    *           如果為空状勤，代表不純正，如果不為空畏铆，代表純在
    *       2.判斷數(shù)據(jù)庫中id為3的客戶的數(shù)量
    *           如果數(shù)量為0雷袋，代表不存在，如果大于0，代表存在
    * */
    @Test
    public void testExists(){
        boolean exists = customerDao.exists(3l);
        System.out.println(exists);
    }
    /*
    * 根據(jù)id查詢用戶
    *  findOne:
    *       em.find()           :立即加載
    * getOne:
    *       em.getReference     :延遲加載
    *       *返回的是一個(gè)客戶的動(dòng)態(tài)代理對象
    *       *什么時(shí)候用楷怒，什么時(shí)候查詢
    * */
    @Test
    @Transactional//保證getOne正常運(yùn)行
    public void testGetOne(){
        Customer one = customerDao.getOne(3l);
        System.out.println(one);
    }
}

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