zoukankan      html  css  js  c++  java
  • springboot08-jpa-mysql

    1.主要pom依赖:

    <!--jpa-->
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-data-jpa</artifactId>
            </dependency>
            <!--mysql-->
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
            </dependency>

    2.userDao:

    public interface UserDao extends JpaRepository<User, Long>{
    
        User findByUserName(String userName);
        User findByUserNameAndPassword(String userName, String password);
    }

    这里继承JpaRepository后,会有主要的增删改查方法,还有查询所有list(), 分页查询list() 等基础方法。如果要自定义方法,可根据jpa标准来定义,比如:

    //根据用户名查询单个用户:  User findOneByUserName(String userName);

    //根据用户名查询多个用户:  List<User> findAllByUserName(String userName);

     3.测试:

    @RunWith(SpringRunner.class)
    @SpringBootTest(classes = MainApp.class)
    public class ServiceTest {
    
        @Autowired
        private UserDao userDao;
        @Autowired
        private UserService userService;
    
        private ObjectMapper objectMapper = new ObjectMapper();
    
        @Test
        public void testAll() throws JsonProcessingException {
    
            this.saveUser();
            this.list();
    
        }
    
        private void saveUser() throws JsonProcessingException {
            User admin = new User();
            admin.setUserName("admin");
            admin.setPassword("admin");
            User adminSave = userDao.save(admin);
            System.out.println("admin save--->:" + objectMapper.writeValueAsString(adminSave));
            User user = new User();
            user.setUserName("user");
            user.setPassword("user");
            User userSave = userDao.save(user);
            System.out.println("user save--->:" + objectMapper.writeValueAsString(userSave));
        }
    
        private void list() throws JsonProcessingException {
            List<User> userList = userService.userList();
            System.out.println("用户列表:" + objectMapper.writeValueAsString(userList));
        }
    
    }

    结果:

    Hibernate: insert into user (password, user_name) values (?, ?)
    admin save--->:{"id":1,"userName":"admin","password":"admin"}
    Hibernate: insert into user (password, user_name) values (?, ?)
    user save--->:{"id":2,"userName":"user","password":"user"}
    
    
    Hibernate: select user0_.id as id1_0_, user0_.password as password2_0_, user0_.user_name as user_nam3_0_ from user user0_
    用户列表:[{"id":1,"userName":"admin","password":"admin"},{"id":2,"userName":"user","password":"user"}]

    源码地址:https://github.com/yangzhenlong/mySpringBootDemo

     
  • 相关阅读:
    Spring Boot ELK Kafka 自定义断路器Circuit-Breaker
    据库主体在该数据库中拥有架构,无法删除解决方法
    AlloyImage
    引用嵌入式DLL方法
    C# C++ 字符串传递
    高效取图片像素的方法
    Microsoft Active Accessibility
    IIS配置支持APK下载
    C# gettime实现
    android快捷键
  • 原文地址:https://www.cnblogs.com/yangzhenlong/p/6547196.html
Copyright © 2011-2022 走看看