springboot + jpa增删改查

目前项目用到springboot + jpa进行持久层处理，就写了几个增删改查的小demo

直接上代码

新增：

        //1、新增
        Dog dog = new Dog();
        dog.setName("李哥");
        dog.setCode(123L);
        dog.setAge(66);
        //dog.setId(16L);
        Dog dog1 = dogDao.save(dog);
        System.out.println(dog1.toString());

修改：

        //2、注解方式修改
        Integer dog1 = dogDao.updateDog(77L, "李哥", 16L);
        System.out.println(dog1.toString());
        //3、编程方式修改（注意：此种方式必须在调用update的方法上加@Transactional,不加会报错）
        Long age = 88L;
        String name = "周姐";//你懂的
        Long id = 16L;
        String sql = "update dog set age = '" + age + "' ,name = '" + name +"' where id = '" + id + "'";
        //获取session
        SessionImplementor session = entityManager.unwrap(SessionImplementor.class);
        //获取connection
        Connection connection = session.connection();
        int i = 0;
        try {
            connection.setAutoCommit(false);
            i = entityManager.createNativeQuery(sql).executeUpdate();
            connection.commit();
            connection.setAutoCommit(true);
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
        System.out.println(i);



    //dao层代码如下

    public interface DogDao extends JpaRepository<Dog, Long> {

        @Query(nativeQuery = true,value = "update dog set age = ?1 ,name = ?2 where id = ?3")
        @Modifying
        @Transactional
        Integer updateDog(Long age,String name,Long id);


    }

删除：

        //批量删除,1、调用deleteInBatch方法批量删除
        List<Long> longList = new ArrayList<>();
        longList.add(1L);
        longList.add(2L);
        longList.add(3L);
        try {
            //获取session
            SessionImplementor session = entityManager.unwrap(SessionImplementor.class);
            //获取connection
            Connection connection = session.connection();
            connection.setAutoCommit(false);
            List<Dog> byId = dogDao.findAllById(longList);
            dogDao.deleteInBatch(byId);
            connection.commit();
            connection.setAutoCommit(true);
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
//
//        //2、通过原生sql批量删除
        int i = entityManager.createNativeQuery("delete from dog where id in (" + 10L + "," + 11L + ")").executeUpdate();
        System.out.println(i);

查询：

        //通过hql查询
        List<Dog> dogs = entityManager.createQuery("from Dog d", Dog.class).getResultList();
        dogs.stream().forEach(System.out::println);

希望可以帮助到你，谢谢！