SpringBoot之数据访问和事务-专题三

SpringBoot之数据访问和事务-专题三

四、数据访问

4.1、springboot整合使用JdbcTemplate

4.1.1 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>
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4.1.2 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
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4.1.3 UserService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);
	}
}
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4.1.4 App类

@SpringBootApplication
public class App {

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

}
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注意: spring-boot-starter-parent要在1.5以上

4.2、springboot整合使用mybatis

4.2.1、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>

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4.2.2、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

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4.2.3、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);
}
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4.2.4、启动方式

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

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

}
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4.2.5、Mybatis整合分页插件

pageHelper

PageHelper 是一款好用的开源免费的 Mybatis 第三方物理分页插件

物理分页

支持常见的 12 种数据库。Oracle,MySql,MariaDB,SQLite,DB2,PostgreSQL,SqlServer 等

支持多种分页方式

支持常见的 RowBounds(PageRowBounds)，PageHelper.startPage 方法调用，Mapper 接口参数调用

Maven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.projectlombok</groupId>
			<artifactId>lombok</artifactId>
		</dependency>

		<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>
		<!-- springboot 整合 pagehelper -->
		<dependency>
			<groupId>com.github.pagehelper</groupId>
			<artifactId>pagehelper-spring-boot-starter</artifactId>
			<version>1.2.5</version>
		</dependency>
		<dependency>
			<groupId>org.apache.commons</groupId>
			<artifactId>commons-lang3</artifactId>
			<version>3.7</version>
		</dependency>
	</dependencies>
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配置文件

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


logging.level.com.example.demo.dao=DEBUG
pagehelper.helperDialect=mysql
pagehelper.reasonable=true
pagehelper.supportMethodsArguments=true
pagehelper.params=count=countSql
pagehelper.page-size-zero=true
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Entity层

@Data
public class User {

	private Integer id;
	private String name;
	private Integer age;
}
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Mapper层

public interface UserMapper {
	@Select("SELECT * FROM USERS ")
	List<User> findUserList();
}
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Service层

@Service
public class UserService {
	@Autowired
	private UserMapper userMapper;


	public PageInfo<User> findUserList(int page, int size) {
		// 开启分页插件,放在查询语句上面
		PageHelper.startPage(page, size);
		List<User> listUser = userMapper.findUserList();
		// 封装分页之后的数据
		PageInfo<User> pageInfoUser = new PageInfo<User>(listUser);
		return pageInfoUser;
	}

}
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Controller层

@RestController
public class IndexController {
	@Autowired
	private UserService userService;

	@RequestMapping("/findUser")
	public PageInfo<User> findUserList(int page, int size) {
		return userService.findUserList(page, size);
	}

}
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启动项目

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

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

}
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4.3、springboot整合使用springjpa

4.3.1 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>
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4.3.2 创建User实体类

@Entity(name = "users")
public class UserEntity {
	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	private Integer id;
	@Column(name = "name")
	private String name;
	@Column(name = "age")
	private Integer age;
}
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4.3.3 创建UserDao

public interface UserDao extends JpaRepository<User, Integer> {
}
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4.3.3 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;
	}

}
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4.3.4 启动项目

@SpringBootApplication
public class JpaApp {

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

}
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4.4、springboot整合多数据源

思考下，你们在项目中有使用到多数据源吗？

原理使用根据包名，加载不同的数据源

4.4.1配置文件中新增两个数据源

###datasource1
spring.datasource.test1.driver-class-name = com.mysql.jdbc.Driver
spring.datasource.test1.jdbc-url = jdbc:mysql://localhost:3306/test01?useUnicode=true&characterEncoding=utf-8
spring.datasource.test1.username = root
spring.datasource.test1.password = root
###datasource2
spring.datasource.test2.driver-class-name = com.mysql.jdbc.Driver
spring.datasource.test2.jdbc-url = jdbc:mysql://localhost:3306/test02?useUnicode=true&characterEncoding=utf-8
spring.datasource.test2.username = root
spring.datasource.test2.password = root
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4.4.2配置文件中新增两个数据源

//DataSource01
@Configuration // 注册到springboot容器中
@MapperScan(basePackages = "com.example.test01", sqlSessionFactoryRef = "test1SqlSessionFactory")
public class DataSource1Config {

	@Bean(name = "test1DataSource")
	@ConfigurationProperties(prefix = "spring.datasource.test1")
	@Primary
	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")
	@Primary
	public SqlSessionTemplate testSqlSessionTemplate(
			@Qualifier("test1SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
		return new SqlSessionTemplate(sqlSessionFactory);
	}

}

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DataSource02

//DataSource2
@Configuration // 注册到springboot容器中
@MapperScan(basePackages = "com.example.test02", sqlSessionFactoryRef = "test2SqlSessionFactory")
public class DataSource2Config {


	@Bean(name = "test2DataSource")
	@ConfigurationProperties(prefix = "spring.datasource.test2")
	public DataSource testDataSource() {
		return DataSourceBuilder.create().build();
	}


	@Bean(name = "test2SqlSessionFactory")
	public SqlSessionFactory testSqlSessionFactory(@Qualifier("test2DataSource") DataSource dataSource)
			throws Exception {
		SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
		bean.setDataSource(dataSource);
		// bean.setMapperLocations(
		// new
		// PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test2/*.xml"));
		return bean.getObject();
	}


	@Bean(name = "test2TransactionManager")
	public DataSourceTransactionManager testTransactionManager(@Qualifier("test2DataSource") DataSource dataSource) {
		return new DataSourceTransactionManager(dataSource);
	}

	@Bean(name = "test2SqlSessionTemplate")
	public SqlSessionTemplate testSqlSessionTemplate(
			@Qualifier("test2SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
		return new SqlSessionTemplate(sqlSessionFactory);
	}

}



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4.4.2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);
}	
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4.4.3 多数据源事务注意事项

在多数据源的情况下，使用@Transactional注解时，应该指定事务管理者

@Transactional(transactionManager = "test2TransactionManager")

4.4.5启动项目

@SpringBootApplication
@MapperScan(basePackages = { "com.example.mapper" })
public class App {
	public static void main(String[] args) {
		SpringApplication.run(App.class, args);
	}
}

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No qualifying bean of type [javax.sql.DataSource] is defined: expected single matching bean but found 2: test1DataSource,test2DataSource

加上@Primary即可。

There was an unexpected error (type=Internal Server Error, status=500).

No qualifying bean of type 'org.springframework.transaction.PlatformTransactionManager' available: expected single matching bean but found 2: test1TransactionManager,test2TransactionManager

指定事务管理器

Springboot1.5的时候 没有默认指向数据源 会报错

Springboot2.0的时候 不报错

五、事物管理

5.1.1SpringBoot整合事物管理

Springboot默认集成事物,只主要在方法上加上@Transactional即可

5.1.2SpringBoot分布式事物管理

使用springboot+jta+atomikos 分布式事物管理

Atomikos 是一个为Java平台提供增值服务的并且开源类事务管理器。

5.1.2.1 新增jta-atomikos依赖

<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-jta-atomikos</artifactId>
</dependency>
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5.1.2.2新增配置文件信息

# Mysql 1
mysql.datasource.test1.url = jdbc:mysql://localhost:3306/test01?useUnicode=true&characterEncoding=utf-8
mysql.datasource.test1.username = root
mysql.datasource.test1.password = root

mysql.datasource.test1.minPoolSize = 3
mysql.datasource.test1.maxPoolSize = 25
mysql.datasource.test1.maxLifetime = 20000
mysql.datasource.test1.borrowConnectionTimeout = 30
mysql.datasource.test1.loginTimeout = 30
mysql.datasource.test1.maintenanceInterval = 60
mysql.datasource.test1.maxIdleTime = 60



# Mysql 2
mysql.datasource.test2.url =jdbc:mysql://localhost:3306/test02?useUnicode=true&characterEncoding=utf-8
mysql.datasource.test2.username =root
mysql.datasource.test2.password =root

mysql.datasource.test2.minPoolSize = 3
mysql.datasource.test2.maxPoolSize = 25
mysql.datasource.test2.maxLifetime = 20000
mysql.datasource.test2.borrowConnectionTimeout = 30
mysql.datasource.test2.loginTimeout = 30
mysql.datasource.test2.maintenanceInterval = 60
mysql.datasource.test2.maxIdleTime = 60

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5.1.2.3 读取配置文件信息

@Data
@ConfigurationProperties(prefix = "mysql.datasource.test1")
public class DBConfig1 {

	private String url;
	private String username;
	private String password;
	private int minPoolSize;
	private int maxPoolSize;
	private int maxLifetime;
	private int borrowConnectionTimeout;
	private int loginTimeout;
	private int maintenanceInterval;
	private int maxIdleTime;
	private String testQuery;
}
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@Data
@ConfigurationProperties(prefix = "mysql.datasource.test2")
public class DBConfig2 {

	private String url;
	private String username;
	private String password;
	private int minPoolSize;
	private int maxPoolSize;
	private int maxLifetime;
	private int borrowConnectionTimeout;
	private int loginTimeout;
	private int maintenanceInterval;
	private int maxIdleTime;
	private String testQuery;
}
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5.1.2.4 创建多数据源

​

@Configuration
// basePackages 最好分开配置 如果放在同一个文件夹可能会报错
@MapperScan(basePackages = "com.example.test01", sqlSessionTemplateRef = "testSqlSessionTemplate")
public class MyBatisConfig1 {

	// 配置数据源
	@Primary
	@Bean(name = "testDataSource")
	public DataSource testDataSource(DBConfig1 testConfig) throws SQLException {
		MysqlXADataSource mysqlXaDataSource = new MysqlXADataSource();
		mysqlXaDataSource.setUrl(testConfig.getUrl());
		mysqlXaDataSource.setPinGlobalTxToPhysicalConnection(true);
		mysqlXaDataSource.setPassword(testConfig.getPassword());
		mysqlXaDataSource.setUser(testConfig.getUsername());
		mysqlXaDataSource.setPinGlobalTxToPhysicalConnection(true);

		AtomikosDataSourceBean xaDataSource = new AtomikosDataSourceBean();
		xaDataSource.setXaDataSource(mysqlXaDataSource);
		xaDataSource.setUniqueResourceName("testDataSource");

		xaDataSource.setMinPoolSize(testConfig.getMinPoolSize());
		xaDataSource.setMaxPoolSize(testConfig.getMaxPoolSize());
		xaDataSource.setMaxLifetime(testConfig.getMaxLifetime());
		xaDataSource.setBorrowConnectionTimeout(testConfig.getBorrowConnectionTimeout());
		xaDataSource.setLoginTimeout(testConfig.getLoginTimeout());
		xaDataSource.setMaintenanceInterval(testConfig.getMaintenanceInterval());
		xaDataSource.setMaxIdleTime(testConfig.getMaxIdleTime());
		xaDataSource.setTestQuery(testConfig.getTestQuery());
		return xaDataSource;
	}

	@Primary
	@Bean(name = "testSqlSessionFactory")
	public SqlSessionFactory testSqlSessionFactory(@Qualifier("testDataSource") DataSource dataSource)
			throws Exception {
		SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
		bean.setDataSource(dataSource);
		return bean.getObject();
	}

	@Primary
	@Bean(name = "testSqlSessionTemplate")
	public SqlSessionTemplate testSqlSessionTemplate(
			@Qualifier("testSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
		return new SqlSessionTemplate(sqlSessionFactory);
	}
}
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@Configuration
@MapperScan(basePackages = "com.example.test02", sqlSessionTemplateRef = "test2SqlSessionTemplate")
public class MyBatisConfig2 {

	// 配置数据源
	@Bean(name = "test2DataSource")
	public DataSource testDataSource(DBConfig2 testConfig) throws SQLException {
		MysqlXADataSource mysqlXaDataSource = new MysqlXADataSource();
		mysqlXaDataSource.setUrl(testConfig.getUrl());
		mysqlXaDataSource.setPinGlobalTxToPhysicalConnection(true);
		mysqlXaDataSource.setPassword(testConfig.getPassword());
		mysqlXaDataSource.setUser(testConfig.getUsername());
		mysqlXaDataSource.setPinGlobalTxToPhysicalConnection(true);

		AtomikosDataSourceBean xaDataSource = new AtomikosDataSourceBean();
		xaDataSource.setXaDataSource(mysqlXaDataSource);
		xaDataSource.setUniqueResourceName("test2DataSource");

		xaDataSource.setMinPoolSize(testConfig.getMinPoolSize());
		xaDataSource.setMaxPoolSize(testConfig.getMaxPoolSize());
		xaDataSource.setMaxLifetime(testConfig.getMaxLifetime());
		xaDataSource.setBorrowConnectionTimeout(testConfig.getBorrowConnectionTimeout());
		xaDataSource.setLoginTimeout(testConfig.getLoginTimeout());
		xaDataSource.setMaintenanceInterval(testConfig.getMaintenanceInterval());
		xaDataSource.setMaxIdleTime(testConfig.getMaxIdleTime());
		xaDataSource.setTestQuery(testConfig.getTestQuery());
		return xaDataSource;
	}

	@Bean(name = "test2SqlSessionFactory")
	public SqlSessionFactory testSqlSessionFactory(@Qualifier("test2DataSource") DataSource dataSource)
			throws Exception {
		SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
		bean.setDataSource(dataSource);
		return bean.getObject();
	}

	@Bean(name = "test2SqlSessionTemplate")
	public SqlSessionTemplate testSqlSessionTemplate(
			@Qualifier("test2SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
		return new SqlSessionTemplate(sqlSessionFactory);
	}
}





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5.1.2.4 启动加载配置

@EnableConfigurationProperties(value = { DBConfig1.class, DBConfig2.class })
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分布式事务，可以预览我的这个链接分布式事务

转载于:https://juejin.im/post/5d063888e51d45778f076d37