我应该在哪里设置AbstractPlatformTransactionManager的标志

Question

我有春季项目，使用此配置：

<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"
    p:driverClassName="oracle.jdbc.driver.OracleDriver" p:url="jdbc:oracle:thin:@127.0.0.1:1521:xe"
    p:username="dev" p:password="****" >
</bean>


<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">

    <property name="dataSource" ref="dataSource" />
     ...
    <property name="jpaVendorAdapter">
        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
    </property>

    <property name="jpaProperties">
        <props>
            <prop key="hibernate.hbm2ddl.auto">update</prop>
        </props>
    </property>
</bean>

<context:component-scan base-package="ge.class.entity">
    <context:include-filter type="annotation" expression="org.springframework.stereotype.Repository" />
</context:component-scan>


<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
    <property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>

<tx:annotation-driven mode="aspectj" transaction-manager="transactionManager" />

我选择JPA事务管理器。在Java代码中我使用EntityManager来持久化对象。

在Spring doc我发现为了启用嵌套事务，我应该将setNestedTransactionAllowed的标志设置为true。

我不明白我应该在哪里写这个？我只是声明了这样的实体经理：

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;

import org.springframework.dao.DataAccessException;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.transaction.annotation.Transactional;

@EnableTransactionManagement()
@Repository
public class MavenDaoImpl implements MavenDao {

    protected EntityManager entityManager;
    public EntityManager getEntityManager() {
        return entityManager;
    }

    @PersistenceContext
    public void setEntityManager(EntityManager entityManager) {
        this.entityManager = entityManager;
    }