SpringBoot 2.0入门（2）

老马的编程之旅

发布于 2022-06-22 12:55:44

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发布于 2022-06-22 12:55:44

SpringBoot 数据访问

1.springboot整合使用JdbcTemplate 1.1 pom文件引入

<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.0.0.RELEASE</version>
	</parent>
	<dependencies>
		<!-- jdbcTemplate 依赖 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-jdbc</artifactId>
		</dependency>
		<!-- mysql 依赖 -->
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
		</dependency>
		<!-- 测试 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		<!-- springboot-web组件 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
	</dependencies>

1.2 application.properties新增配置

spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

1.3编写一个测试类

@Service
public class UserServiceImpl implements UserService {
	@Autowired
	private JdbcTemplate jdbcTemplate;
	public void createUser(String name, Integer age) {
		jdbcTemplate.update("insert into users values(null,?,?);", name, age);
	}
}

@SpringBootApplication
public class App {

	public static void main(String[] args) {
		SpringApplication.run(App.class, args);
	}

}

注意: spring-boot-starter-parent要在1.5以上

2.springboot整合使用mybatis 2.1 pom文件引入

<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.0.0.RELEASE</version>
	</parent>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter</artifactId>
		</dependency>
		<!-- 测试 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>org.mybatis.spring.boot</groupId>
			<artifactId>mybatis-spring-boot-starter</artifactId>
			<version>1.1.1</version>
		</dependency>
		<!-- mysql 依赖 -->
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
		</dependency>
		<!-- springboot-web组件 -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
	</dependencies>

2.2 配置文件引入

spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

2.3 Mapper代码

public interface UserMapper {
	@Select("SELECT * FROM USERS WHERE NAME = #{name}")
	User findByName(@Param("name") String name);
	@Insert("INSERT INTO USERS(NAME, AGE) VALUES(#{name}, #{age})")
	int insert(@Param("name") String name, @Param("age") Integer age);
}

2.4 启动方式

@MapperScan("com.itma.mapper")
@SpringBootApplication
public class MybatisApp {

	public static void main(String[] args) {
		SpringApplication.run(MybatisApp.class, args);
	}

}

3.springboot整合使用springjpa 3.1 pom文件引入依赖

<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.0.0.RELEASE</version>
	</parent>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-jpa</artifactId>
		</dependency>
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
	</dependencies>

3.2 创建User实体类

@Entity(name = "users")
public class User {
	@Id
	@GeneratedValue
	private Integer id;
	@Column(name = "name")
	private String name;
	@Column(name = "age")
	private Integer age;
       // get set
}

3.3 创建UserDao

public interface UserDao extends JpaRepository<User, Integer> {
}

3.4 创建IndexController

@RestController
public class IndexController {
	@Autowired
	private UserDao userDao;

	@RequestMapping("/jpaFindUser")
	public Object jpaIndex(User user) {
		Optional<User> userOptional = userDao.findById(user.getId());
		User reusltUser = userOptional.get();
		return reusltUser == null ? "没有查询到数据" : reusltUser;
	}

}

3.5 启动项目

EnableJpaRepositories("com.itma.dao")
@EntityScan(basePackages = "com.itma.entity")
@SpringBootApplication
public class JpaApp {

	public static void main(String[] args) {
		SpringApplication.run(JpaApp.class, args);
	}

}

4.springboot整合多数据源 4.1 配置文件中新增两个数据源

spring.datasource.test1.driverClassName = com.mysql.jdbc.Driver
spring.datasource.test1.url = jdbc:mysql://localhost:3306/test01?useUnicode=true&characterEncoding=utf-8
spring.datasource.test1.username = root
spring.datasource.test1.password = root

spring.datasource.test2.driverClassName = com.mysql.jdbc.Driver
spring.datasource.test2.url = jdbc:mysql://localhost:3306/test02?useUnicode=true&characterEncoding=utf-8
spring.datasource.test2.username = root
spring.datasource.test2.password = root

4.2 配置文件中新增两个数据源

@Configuration // 注册到springboot容器中
@MapperScan(basePackages = "com.itma.user1", sqlSessionFactoryRef = "test1SqlSessionFactory")
public class DataSource1Config {


	@Bean(name = "test1DataSource")
	@Primary
	@ConfigurationProperties(prefix = "spring.datasource.test1")
	public DataSource testDataSource() {
		return DataSourceBuilder.create().build();
	}


	@Bean(name = "test1SqlSessionFactory")
	@Primary
	public SqlSessionFactory testSqlSessionFactory(@Qualifier("test1DataSource") DataSource dataSource)
			throws Exception {
		SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
		bean.setDataSource(dataSource);
//		bean.setMapperLocations(
//				new PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test1/*.xml"));
		return bean.getObject();
	}


	@Bean(name = "test1TransactionManager")
	@Primary
	public DataSourceTransactionManager testTransactionManager(@Qualifier("test1DataSource") DataSource dataSource) {
		return new DataSourceTransactionManager(dataSource);
	}

	@Bean(name = "test1SqlSessionTemplate")
	public SqlSessionTemplate testSqlSessionTemplate(
			@Qualifier("test1SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
		return new SqlSessionTemplate(sqlSessionFactory);
	}

}


@Configuration // 注册到springboot容器中
@MapperScan(basePackages = "com.itma.user1", sqlSessionFactoryRef = "test1SqlSessionFactory")
public class DataSource1Config {

	
	@Bean(name = "test1DataSource")
	@Primary
	@ConfigurationProperties(prefix = "spring.datasource.test1")
	public DataSource testDataSource() {
		return DataSourceBuilder.create().build();
	}


	@Bean(name = "test1SqlSessionFactory")
	@Primary
	public SqlSessionFactory testSqlSessionFactory(@Qualifier("test1DataSource") DataSource dataSource)
			throws Exception {
		SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
		bean.setDataSource(dataSource);
//		bean.setMapperLocations(
//				new PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test1/*.xml"));
		return bean.getObject();
	}

	
	@Bean(name = "test1TransactionManager")
	@Primary
	public DataSourceTransactionManager testTransactionManager(@Qualifier("test1DataSource") DataSource dataSource) {
		return new DataSourceTransactionManager(dataSource);
	}

	@Bean(name = "test1SqlSessionTemplate")
	public SqlSessionTemplate testSqlSessionTemplate(
			@Qualifier("test1SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
		return new SqlSessionTemplate(sqlSessionFactory);
	}

}

4.3 创建分包Mapper

public interface User1Mapper {
	@Insert("insert into users values(null,#{name},#{age});")
	public int addUser(@Param("name") String name, @Param("age") Integer age);
}

4.4 启动项目

@ComponentScan(basePackages = "com.itma")
@EnableAutoConfiguration
public class App {
	public static void main(String[] args) {
		SpringApplication.run(App.class, args);
	}
}

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原始发表：2018-10-16，如有侵权请联系 cloudcommunity@tencent.com 删除

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