使用注解实现：
连接mysql数据库对数据库的增删改查事务管理 1.环境准备 1.1 项目目录
1.2 pom.xml配置1.3 AppConfig.class配置4.0.0 com.itheima AOP_z_tx_pure_anno_01 1.0-SNAPSHOT 11 11 junit junit 4.12 test org.springframework spring-context 5.1.2.RELEASE mysql mysql-connector-java 5.1.47 com.alibaba druid 1.1.23 org.mybatis mybatis 3.5.6 org.mybatis mybatis-spring 2.0.6 org.springframework spring-jdbc 5.1.2.RELEASE org.slf4j slf4j-api 1.7.20 ch.qos.logback logback-classic 1.2.3 ch.qos.logback logback-core 1.2.3 org.springframework spring-test 5.1.2.RELEASE org.aspectj aspectjweaver 1.9.4
@EnableTransactionManagement
启注解事务管理，等同于xml配置方式的
使用注解 @EnableTransactionManagement 开启事务支持后，然后在访问数据库的Service方法上添加注解 @Transactional 便可。
关于事务管理器，不管是JPA还是JDBC等都实现自接口 PlatformTransactionManager 如果你添加的是 spring-boot-starter-jdbc 依赖，框架会默认注入 DataSourceTransactionManager 实例。如果你添加的是 spring-boot-starter-data-jpa 依赖，框架会默认注入 JpaTransactionManager 实例。
@MapperScan(“com.itheima.dao”)
作用：指定要变成实现类的接口所在的包，然后包下面的所有接口在编译之后都会生成相应的实现类
添加位置：是在Springboot启动类上面添加
@PropertySource(“classpath:db.properties”)
导入properties文件
@ComponentScan(“com.itheima”)
根据定义的扫描路径，把符合扫描规则的类装配到spring容器中
@Configuration
用于定义配置类，可替换xml配置文件
@Value
注入简单类型的变量。复杂类型使用@Autowired注入
package com.itheima.config;
import com.alibaba.druid.pool.DruidDataSource;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import javax.sql.DataSource;
@EnableTransactionManagement
@MapperScan("com.itheima.dao")
@PropertySource("classpath:db.properties")
@ComponentScan("com.itheima")
@Configuration
public class AppConfig {
@Value("${db.driverClass}")
private String driverClass;
@Value("${db.url}")
private String url;
@Value("${db.username}")
private String username;
@Value("${db.password}")
private String password;
//2.创建数据源bean对象 放入IOC容器管理
@Bean
public DataSource dataSource(){
DruidDataSource druidDataSource = new DruidDataSource();
druidDataSource.setDriverClassName(driverClass);
druidDataSource.setUrl(url);
druidDataSource.setUsername(username);
druidDataSource.setPassword(password);
return druidDataSource;
}
//3.加载数据源 创建SqlSessionFactory bean对象 交给Spring IOC容器管理
@Bean
public SqlSessionFactoryBean sqlSessionFactory(DataSource dataSource){
SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
sqlSessionFactoryBean.setDataSource(dataSource);
//细节2：设置别名
sqlSessionFactoryBean.setTypeAliasesPackage("com.itheima.bean");
return sqlSessionFactoryBean;
}
//4.创建事务管理员对象
@Bean
public PlatformTransactionManager transactionManager(DataSource dataSource){
DataSourceTransactionManager dataSourceTransactionManager = new DataSourceTransactionManager();
dataSourceTransactionManager.setDataSource(dataSource);
return dataSourceTransactionManager;
}
}
1.4 业务调用概述
Service ➡️ Dao ➡️ SQL
2.bean Accountpackage com.itheima.bean;
public class Account {
private Integer id;
private String name;
private Integer money;
public Account() {
}
public Account(Integer id, String name, Integer money) {
this.id = id;
this.name = name;
this.money = money;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getMoney() {
return money;
}
public void setMoney(Integer money) {
this.money = money;
}
@Override
public String toString() {
return "Account{" +
"id=" + id +
", name='" + name + ''' +
", money=" + money +
'}';
}
}
3.dao
AccountDao 接口
package com.itheima.dao;
import com.itheima.bean.Account;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;
import java.util.List;
public interface AccountDao {
@Select("select * from tb_user")
List findAll();
@Update("update tb_user set money = money - #{money} where name = #{name}")
int kouqian(@Param("name") String name,@Param("money") int money);
@Update("update tb_user set money = money + #{money} where name = #{name}")
int jiaqian(@Param("name") String name,@Param("money") int money);
}
LogDao 接口
package com.itheima.dao;
import org.apache.ibatis.annotations.Insert;
public interface LogDao {
@Insert("insert into tb_log(info) values(#{info})")
int writeLog(String info);
}
4.service
AccountService 接口
package com.itheima.service;
import com.itheima.bean.Account;
import java.util.List;
public interface AccountService {
List findAll();
void transfer(String from, String to, int money);
}
LogService 接口
package com.itheima.service;
public interface LogService {
void writeLog(String info);
}
AccountServiceImpl 实现类
在该类中，先实现AccountService接口中的方法。然后在重写的方法中调用Dao层的AccountDao接口中的方法。当IOC容器在使用Service层的方法时，最终要实现Dao层的实现类中的重写方法。
调用链路：IOC ➡️ serviceDao ➡️ serviceDaoImpl ➡️ Dao ➡️ DaoImpl
@Transactional
该注解表示开启事务管理
如果打在类上，则表示对类中所有的方法进行事务管理
如果打在类中某个方法上，则表示对某个方法进行事务管理
@Service
该注解表示将该类注入到IOC容器中
@Autowired
该注解表示自动注入依赖，依赖类无需使用@Component注解
package com.itheima.service.impl;
import com.itheima.bean.Account;
import com.itheima.dao.AccountDao;
import com.itheima.dao.LogDao;
import com.itheima.service.AccountService;
import com.itheima.service.LogService;
import org.aspectj.lang.annotation.Around;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import java.util.List;
@Transactional
@Service
public class AccountServiceImpl implements AccountService {
@Autowired
private AccountDao accountDao;
@Autowired
private LogService logService;
@Override
public List findAll() {
return accountDao.findAll();
}
@Override
public void transfer(String from, String to, int money) {
try {
accountDao.kouqian(from, money);
//int a = 1/0;
accountDao.jiaqian(to, money);
} finally {
String info = from + "->" + to + ": " + money + "-RMB";
logService.writeLog(info);
}
}
}
LogServiceImpl 实现类
@Transactional(propagation = Propagation.REQUIRES_NEW)
propagation = Propagation.REQUIRES_NEW：表示无论如何都开启新事务
package com.itheima.service.impl;
import com.itheima.dao.LogDao;
import com.itheima.service.LogService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;
@Transactional(propagation = Propagation.REQUIRES_NEW)
@Service
public class LogServiceImpl implements LogService {
@Autowired
private LogDao logDao;
@Override
public void writeLog(String info) {
logDao.writeLog(info);
}
}
