SpringSource与2011年6月8号发布了Spring 3.1.0 M2，TEAM BLOG与6月9号和6月10号连续发布两篇博文Spring Framework 3.1 M2 released，Spring 3.1 M2: Configuration Enhancements来介绍。这其中Chris Beans的文章介绍了如何整合Hibernate，说在M2中新引入了一个类AnnotationSessionFactoryBuilder来简化code-based的Spring配置方式。结合到具体项目中：
@Configuration
@EnableTransactionManagement
public class DataConfig {
@Inject
private Environment environment;
@Inject
private DataSource dataSource;
@Bean
public JdbcTemplate jdbcTemplate() {
return new JdbcTemplate(dataSource);
}
@Bean
public SimpleJdbcInsert simpleJdbcInsert() {
return new SimpleJdbcInsert(dataSource);
}
// 3.1.0.M2
@Bean
public SessionFactory sessionFactory() throws Exception {
Properties hibernateProperties = new Properties();
hibernateProperties.put("hibernate.dialect", environment.getProperty("hibernate.dialect"));
hibernateProperties.put("hibernate.show_sql", environment.getProperty("hibernate.show_sql"));
hibernateProperties.put("hibernate.generate_statistics", environment.getProperty("hibernate.generate_statistics"));
hibernateProperties.put("hibernate.format_sql", environment.getProperty("hibernate.format_sql"));
return new AnnotationSessionFactoryBuilder()
.setDataSource(dataSource)
.setPackagesToScan(environment.getProperty("hibernate.packagesToScan")
.setHibernateProperties(hibernateProperties)
.buildSessionFactory();
}
@Bean
public PlatformTransactionManager transactionManager() throws Exception {
HibernateTransactionManager bean = new HibernateTransactionManager();
bean.setSessionFactory(sessionFactory());
return bean;
}
@Configuration
@Profile("dev")
static class Development {
@Inject
private Environment environment;
@Bean(destroyMethod="close")
public DataSource dataSource() {
DruidDataSource dataSource = new DruidDataSource();
dataSource.setDriverClassName(environment.getProperty("jdbc.driverClassName"));
dataSource.setUrl(environment.getProperty("jdbc.url"));
dataSource.setUsername(environment.getProperty("jdbc.username"));
dataSource.setPassword(environment.getProperty("jdbc.password"));
return dataSource;
}
}
}
但是经过测试，这样配置在service方法抛出异常后事务是不能回滚的！
问题似乎在最近刚出的RC1版本中得到了修正，在RC1版本中，AnnotationSessionFactoryBuilder类已经悄然从发布包中移除了，于是我们只能使用原始的AnnotationSessionFactoryBean类来配置：
@Configuration
@EnableTransactionManagement
public class DataConfig {
@Inject
private Environment environment;
@Inject
private DataSource dataSource;
@Bean
public JdbcTemplate jdbcTemplate() {
return new JdbcTemplate(dataSource);
}
@Bean
public SimpleJdbcInsert simpleJdbcInsert() {
return new SimpleJdbcInsert(dataSource);
}
// 3.1.0.RC1
@Bean
public IdTransferringMergeEventListener merge() {
IdTransferringMergeEventListener bean = new IdTransferringMergeEventListener();
return bean;
}
@Bean
public AnnotationSessionFactoryBean annotationSessionFactoryBean() {
Properties hibernateProperties = new Properties();
hibernateProperties.setProperty("hibernate.dialect", environment.getProperty("hibernate.dialect"));
hibernateProperties.setProperty("hibernate.show_sql", environment.getProperty("hibernate.show_sql"));
hibernateProperties.setProperty("hibernate.generate_statistics", environment.getProperty("hibernate.generate_statistics"));
hibernateProperties.setProperty("hibernate.format_sql", environment.getProperty("hibernate.format_sql"));
AnnotationSessionFactoryBean bean = new AnnotationSessionFactoryBean();
bean.setDataSource(dataSource);
bean.setPackagesToScan(new String[] { environment.getProperty("hibernate.packagesToScan") });
bean.setHibernateProperties(hibernateProperties);
// optional
Map<String, Object> eventListeners = new HashMap<String, Object>();
eventListeners.put("merge", merge());
bean.setEventListeners(eventListeners);
return bean;
}
@Bean
public PlatformTransactionManager transactionManager() {
HibernateTransactionManager bean = new HibernateTransactionManager();
bean.setSessionFactory(annotationSessionFactoryBean().getObject());
return bean;
}
@Configuration
@Profile("dev")
static class Development {
@Inject
private Environment environment;
@Bean(destroyMethod="close")
public DataSource dataSource() {
DruidDataSource dataSource = new DruidDataSource();
dataSource.setDriverClassName(environment.getProperty("jdbc.driverClassName"));
dataSource.setUrl(environment.getProperty("jdbc.url"));
dataSource.setUsername(environment.getProperty("jdbc.username"));
dataSource.setPassword(environment.getProperty("jdbc.password"));
return dataSource;
}
}
}
经过测试，这样的配置事务是可以回滚的。因为官方JIRA中没有找到对应的BUG列表，只能揣测开发团队内部发现此问题，但是有点想不明白为什么当初要“隆重”的介绍这个AnnotationSessionFactoryBuilder类出场。
然后很自然地联想到，如果直接在M2版本中使用上面这个RC1版本的配置，事务是否能回滚？答案是能回滚。
最后注意到在SPRING FRAMEWORK 3.1 RC1 RELEASED一文中有个叫Tobias的也注意到了AnnotationSessionFactoryBuilder类从RC1版中移除了，不知道他之前有没有碰到事务失效的问题？XD
补充（2011.10.22 15:10）：
通过P6SPY抓取底层JDBC发送给数据库的sql发现有差异，如下：
事务失效
20111022 15:05:00,429|2|1|statement|insert into t_primary_keys(pk_key, pk_value) values('t_teacher', 0)
20111022 15:05:00,434|4|1|statement|update t_primary_keys set pk_value = 1 where pk_value = 0 and pk_key = 't_teacher'
20111022 15:05:00,436|1|1|commit|
20111022 15:05:00,442|1|1|statement|update t_primary_keys set pk_value = 2 where pk_value = 1 and pk_key = 't_teacher'
20111022 15:05:00,443|0|1|commit|
20111022 15:05:00,472|1|1|statement|insert into t_primary_keys(pk_key, pk_value) values('t_student', 0)
20111022 15:05:00,477|5|1|statement|update t_primary_keys set pk_value = 1 where pk_value = 0 and pk_key = 't_student'
20111022 15:05:00,492|15|1|commit|
20111022 15:05:00,494|0|1|statement|update t_primary_keys set pk_value = 2 where pk_value = 1 and pk_key = 't_student'
20111022 15:05:00,495|0|1|commit|
20111022 15:05:00,523|3|1|statement|insert into t_teacher (name, id) values ('teacher', 1)
20111022 15:05:00,535|11|1|statement|insert into t_student (name, id) values ('sssssssssssssssssssssss', 1)
事务成功
20111022 15:09:01,162|1|1|statement|update t_primary_keys set pk_value = 3 where pk_value = 2 and pk_key = 't_teacher'
20111022 15:09:01,163|1|1|commit|
20111022 15:09:01,186|1|1|statement|update t_primary_keys set pk_value = 3 where pk_value = 2 and pk_key = 't_student'
20111022 15:09:01,187|1|1|commit|
20111022 15:09:01,214|2|0|statement|insert into t_teacher (name, id) values ('teacher', 2)
20111022 15:09:01,226|11|0|statement|insert into t_student (name, id) values ('sssssssssssssssssssssss', 2)
20111022 15:09:01,240|1|0|rollback|
从中不难看出，事务成功的sql中发出了rollback，而事务失效的既没有发出rollback，也没有发出commit，这个时候jdbc链接是否释放，存不存在内存泄漏的情况暂时不得而知，等以后有时间在深入研究一下。