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当使用嵌套的Spring事务时，我发现了一些奇怪的行为：在同一个类中，如果注释为@Transactional的方法调用另一个也注释为@Transactional的方法，则不使用第二个注释。Spring上的嵌套事务
让我们考虑下面的类：
public class Main {
public static void main(String[] args) {
ApplicationContext context = new AnnotationConfigApplicationContext(Config.class);
final Main main = context.getBean(Main.class);
// First Op
System.out.println("Single insert: " + main.singleInsert());
// Second Op
main.batchInsert();
// Third Op
main.noTransBatchInsert();
}
@PersistenceContext
private EntityManager pm;
@Transactional(propagation=Propagation.REQUIRED)
public void batchInsert() {
System.out.println("batchInsert");
System.out.println("First insert: " + singleInsert());
System.out.println("Second insert: " + singleInsert());
}
public void noTransBatchInsert() {
System.out.println("noTransBatchInsert");
System.out.println("First insert: " + singleInsert());
System.out.println("Second insert: " + singleInsert());
}
@Transactional(propagation=Propagation.REQUIRES_NEW)
public int singleInsert() {
System.out.println("singleInsert");
Pojo p = new Pojo();
pm.persist(p);
return p.getId();
}
}
实体，如果下面的类：
@Entity
public class Pojo {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private int id;
@Override
public String toString() {
return "Pojo: " + id;
}
public int getId() {
return id;
}
}
和字符串部分的applicationContext.xml：
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p" xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context" xmlns:jee="http://www.springframework.org/schema/jee"
xmlns:tx="http://www.springframework.org/schema/tx" xmlns:task="http://www.springframework.org/schema/task"
xsi:schemaLocation="
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.0.xsd">
<tx:annotation-driven />
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean">
<property name="persistenceUnitName" value="MyPersistenceUnit" />
</bean>
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
</beans>
和配置类（我可以将它合并到applicationContext.xml中）。
@Configuration
@ImportResource("/META-INF/applicationContext.xml")
public class Config {
@Bean
public Main main() {
return new Main();
}
}
为了完整persistence.xml文件：
<persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd" version="2.0">
<persistence-unit name="MyPersistenceUnit" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<properties>
<property name="hibernate.hbm2ddl.auto" value="create" />
<property name="hibernate.show_sql" value="true" />
<property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect" />
<property name="hibernate.connection.driver_class" value="org.h2.Driver" />
<property name="hibernate.connection.url" value="jdbc:h2:mem:TestDSJPA2;DB_CLOSE_DELAY=-1;LOCK_MODE=0" />
<!--<property name="hibernate.connection.url" value="jdbc:h2:mem:TestDSJPA2;DB_CLOSE_DELAY=-1;LOCK_MODE=0" />-->
<property name="hibernate.connection.username" value="sa" />
<property name="hibernate.connection.password" value="" />
<property name="hibernate.connection.autocommit" value="false"/>
<property name="hibernate.c3p0.min_size" value="5" />
<property name="hibernate.c3p0.max_size" value="20" />
<property name="hibernate.c3p0.timeout" value="300" />
<property name="hibernate.c3p0.max_statements" value="50" />
<property name="hibernate.c3p0.idle_test_period" value="3000" />
</properties>
</persistence-unit>
</persistence>
所以在主类，因为预计是在一个新的事务进行第一次操作。输出（包括一些调试消息）是：
DEBUG o.h.transaction.JDBCTransaction - begin
singleInsert
DEBUG o.h.transaction.JDBCTransaction - commit
Single insert: 1
第二次行动给出了以下的输出：
batchInsert
singleInsert
DEBUG o.h.transaction.JDBCTransaction - begin
First insert: 2
singleInsert
Second insert: 3
DEBUG
这不是我所期待的，因为与@Transactional(propagation=Propagation.REQUIRES_NEW)注释singleInsert我希望新的交易为每次调用创建，因为两个插入都使用相同的顶级事务，所以不会发生这种情况。
第三操作失败，以及没有交易可言创建：
noTransBatchInsert
singleInsert
DEBUG o.h.e.def.AbstractSaveEventListener - delaying identity-insert due to no transaction in progress
First insert: 0
singleInsert
DEBUG o.h.e.def.AbstractSaveEventListener - delaying identity-insert due to no transaction in progress
Second insert: 0
在@Configuration豆弹簧确保调用对同一类中proxified这显然是这里没有发生的方法。有没有办法改变这种行为？