网络相册开发（5）——标注、Spring的“零配置”

首先让我们复习一下常用的标注

 

用于描述hibernate映射关系的标注，告别*.hbm.xml

@Entity(name = “***")

@Id
@Column

 

下面四个标注用来定义 bean, 自动根据 bean 的类名生成一个首字母小写的 bean

@Component 标注普通的Spring Bean类

@Controller 标注控制器组件类

@Service 标注业务逻辑组件类

@Repository 标注一个DAO组件类

 

@Autowired 则是自动注入依赖的类, 它会在类路径中找成员对应的类/接口的实现类,

 

我们在BaseTest.java中使用过的

@ContextConfiguration

 

用来管理事务的

@Transactional

 

为保证标记可以运行，进一步修改ApplicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:aop="http://www.springframework.org/schema/aop"
	xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd 
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd 
		http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd 
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd"
	default-lazy-init="true">
	<context:annotation-config />



	<bean id="dataSource"
		class="org.apache.commons.dbcp.BasicDataSource">
		<property name="driverClassName">
			<value>com.mysql.jdbc.Driver</value>
		</property>
		<property name="url">
			<value>
				jdbc:mysql://localhost/sw?createDatabaseIfNotExist=true&amp;useUnicode=true&amp;characterEncoding=utf-8
			</value>
		</property>
		<property name="username">
			<value>root</value>
		</property>
		<property name="password">
			<value>mysql</value>
		</property>
	</bean>

	<!-- JPA EntityManagerFactoryBean for EntityManager-->

	<bean id="myEntityManagerFactory"
		class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
		<property name="dataSource" ref="dataSource" />
		<property name="jpaVendorAdapter">
			<bean
				class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
				<property name="showSql" value="true" />
				<property name="generateDdl" value="true" />
			</bean>
		</property>
	</bean>

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

	<bean id="albumDao" class="net.sw.album.dao.jpa.AlbumDaoJpa">
		<property name="entityManagerFactory"
			ref="myEntityManagerFactory" />
	</bean>

	<bean id="photoDao" class="net.sw.album.dao.jpa.PhotoDaoJpa">
		<property name="entityManagerFactory"
			ref="myEntityManagerFactory" />
	</bean>

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


	<context:component-scan
		base-package="net.sw.album.service.impl" />


</beans>

 

albumDao、photoDao这两个bean的声明我没有找到使用标注把它们从xml中消除的方法，他们需要注入entityManagerFactory，这个属性是继承自他们的父类JpaDaoSupport。没办法控制，失败。