Spring integrates Mybatis&Junit unit test

Spring integrates Mybatis&Junit unit test

1. Spring integrates Mybatis [key]

1.1 Thought Analysis

problem import

Who is the core object of mybatis for data layer operations?

1.1.1 MyBatis program core object analysis

1.1.2 Integrate MyBatis

Use SqlSessionFactoryBean to encapsulate the environment information required by SqlSessionFactory

Use MapperScannerConfigurer to load the Dao interface, create a proxy object and save it in the IOC container

1.2 Code implementation

problem import

Question 1: What is the dependency of Spring integrating mybatis?

Question 2: Which two beans need to be managed and configured by Spring to integrate mybatis, and what are the functions of these two beans?

【Pre-work】

Add spring-context, druid, mybatis, mysql-connector-java and other basic dependencies in pom.xml.
Prepare the service and dao layer basic code

public interface AccountService {
    
    

    void save(Account account);

    void delete(Integer id);

    void update(Account account);

    List<Account> findAll();

    Account findById(Integer id);

}
@Service
public class AccountServiceImpl implements AccountService {
    
    

    @Autowired
    private AccountDao accountDao;

    public void save(Account account) {
    
    
        accountDao.save(account);
    }

    public void update(Account account){
    
    
        accountDao.update(account);
    }

    public void delete(Integer id) {
    
    
        accountDao.delete(id);
    }

    public Account findById(Integer id) {
    
    
        return accountDao.findById(id);
    }

    public List<Account> findAll() {
    
    
        return accountDao.findAll();
    }
}
public interface AccountDao {
    
    

    @Insert("insert into tbl_account(name,money)values(#{name},#{money})")
    void save(Account account);

    @Delete("delete from tbl_account where id = #{id} ")
    void delete(Integer id);

    @Update("update tbl_account set name = #{name} , money = #{money} where id = #{id} ")
    void update(Account account);

    @Select("select * from tbl_account")
    List<Account> findAll();

    @Select("select * from tbl_account where id = #{id} ")
    Account findById(Integer id);
}

[Step 1] Import Spring to integrate Mybatis dependencies

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jdbc</artifactId>
    <version>5.2.10.RELEASE</version>
</dependency>

<dependency>
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis-spring</artifactId>
    <version>1.3.0</version>
</dependency>

[Step 2] Create JdbcConfig to configure DataSource data source

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/spring_db?useSSL=false
jdbc.username=root
jdbc.password=root

public class JdbcConfig {
    
    
    @Value("${jdbc.driver}")
    private String driver;
    @Value("${jdbc.url}")
    private String url;
    @Value("${jdbc.username}")
    private String userName;
    @Value("${jdbc.password}")
    private String password;

    @Bean
    public DataSource dataSource(){
    
    
        DruidDataSource ds = new DruidDataSource();
        ds.setDriverClassName(driver);
        ds.setUrl(url);
        ds.setUsername(userName);
        ds.setPassword(password);
        return ds;
    }
}

[Step 3] Create MybatisConfig to integrate mybatis

public class MybatisConfig {
    
    
    //定义bean，SqlSessionFactoryBean，用于产生SqlSessionFactory对象
    @Bean
    public SqlSessionFactoryBean sqlSessionFactory(DataSource dataSource){
    
    
        SqlSessionFactoryBean ssfb = new SqlSessionFactoryBean();
        ssfb.setTypeAliasesPackage("com.itheima.domain");
        ssfb.setDataSource(dataSource);
        return ssfb;
    }
    //定义bean，返回MapperScannerConfigurer对象
    @Bean
    public MapperScannerConfigurer mapperScannerConfigurer(){
    
    
        MapperScannerConfigurer msc = new MapperScannerConfigurer();
        msc.setBasePackage("com.itheima.dao");
        return msc;
    }
}

[Step 4] Create a SpringConfig main configuration class for package scanning and loading other configuration classes

@Configuration
@ComponentScan("com.itheima")
//@PropertySource：加载类路径jdbc.properties文件
@PropertySource("classpath:jdbc.properties")
@Import({
    
    JdbcConfig.class,MybatisConfig.class})
public class SpringConfig {
    
    
}

[Step 5] Define the test class for testing

public class App {
    
    
    public static void main(String[] args) {
    
    
        ApplicationContext ctx = new AnnotationConfigApplicationContext(SpringConfig.class);

        AccountService accountService = ctx.getBean(AccountService.class);

        Account ac = accountService.findById(1);
        System.out.println(ac);
    }
}

2. Spring integrates Junit unit testing [key]

problem import

What are the two annotation functions of Spring integrating Junit?

[Step 1] Import the integrated dependency coordinate spring-test

<!--junit-->
<dependency>
  <groupId>junit</groupId>
  <artifactId>junit</artifactId>
  <version>4.12</version>
</dependency>
<!--spring整合junit-->
<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-test</artifactId>
  <version>5.1.9.RELEASE</version>
</dependency>

[Step 2] Use Spring to integrate Junit-specific class loaders

[Step 3] Load the configuration file or configuration class

//【第二步】使用Spring整合Junit专用的类加载器
@RunWith(SpringJUnit4ClassRunner.class)
//【第三步】加载配置文件或者配置类
@ContextConfiguration(classes = {
    
    SpringConfiguration.class}) //加载配置类
//@ContextConfiguration(locations={"classpath:applicationContext.xml"})//加载配置文件
public class AccountServiceTest {
    
    
    //支持自动装配注入bean
    @Autowired
    private AccountService accountService;

    @Test
    public void testFindById(){
    
    
        System.out.println(accountService.findById(1));
    }

    @Test
    public void testFindAll(){
    
    
        System.out.println(accountService.findAll());
    }
}

Note: The dependency of junit must be at least version 4.12, it can be version 4.13, otherwise the following exception will occur: