Spring学习参考

注解

  @Async：http://blog.csdn.net/blueheart20/article/details/44648667

EntityManager:

For the @PersistenceContext EntityManager entityManager; approach, add tx:annotation-driven to your .xml configuration and mark your methods where you use entityManager as @Transactional.

生成entityManagerFactory的三种方式（配置文件）：

http://www.cnblogs.com/beiyeren/archive/2013/01/23/2873210.html

http://docs.spring.io/spring/docs/3.2.x/spring-framework-reference/html/orm.html#orm-jpa