Spring-tx-@EnableTransactionManagement注解

xml形式的spring配置使用tx标签来开启事务
而注解形式的spring配置，则使用@EnableTransactionManagement注解

其实本文要说的内容，在该注解的注释当中都有，例如下面这个代码

@Component
public class Creater1 {

  @Autowired
  JdbcTemplate jdbcTemplate;

  @Transactional(rollbackFor = Exception.class)
  public void create() {
    jdbcTemplate.update("insert into t1(value) values ('HAHA')");
    throw new RuntimeException("抛异常就回滚");
  }
}

import javax.sql.DataSource;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import com.zaxxer.hikari.HikariDataSource;

@Configuration
@EnableTransactionManagement
public class TestMain {

  @Bean
  public DataSource dataSource() {
    HikariDataSource ds = new HikariDataSource();
    ds.setJdbcUrl("jdbc:mysql://localhost:3306/swttest?serverTimezone=UTC&&useSSL=false");
    ds.setUsername("root");
    ds.setPassword("123456");
    return ds;
  }

  @Bean
  public JdbcTemplate jdbcTemplate() {
    JdbcTemplate jdbc = new JdbcTemplate();
    jdbc.setDataSource(dataSource());
    return jdbc;
  }

  @Bean
  public PlatformTransactionManager platformTransactionManager() {
    return new DataSourceTransactionManager(dataSource());
  }

  public static void main(String[] args) throws Throwable {
    // 依赖容器的话必须要开启@EnableTransactionManagement注解，表示告诉spring我要使用事务
    AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(
        "com.example.studyintegration.spring.Transcation.TranscationStatus");
    Creater1 tt = ctx.getBean(Creater1.class);
    tt.create();
  }
}

上面就是使用该注解的方式，开启事务，抛异常就会回滚，需要注意的地方：
@EnableTransactionManagement注解必须配合@Configuration注解使用，否则不会生效事务功能

日记：@Configuration注解等同于java版本的xml文件，以前xml版本的tx标签是写到xml文件中的，而EnableTransactionManagement等同于tx标签，这也更加印证了Configuration注解就是一个java抽象的xml文件

在@Configuration的注释中其中就说明了这一项

Enabling built-in Spring features using @Enable annotations
Spring features such as asynchronous method execution, 
scheduled task execution,
annotation driven transaction management, 
and even Spring MVC can be enabled andconfigured from @Configuration classes using their respective "@Enable"annotations. 
See @EnableAsync, 
@EnableScheduling, 
@EnableTransactionManagement,
@EnableAspectJAutoProxy,
and @EnableWebMvcfor details.