从spring3.0开始，Spring将JavaConfig整合到核心模块，普通的POJO只需要标注@Configuration注解，就可以成为spring配置类，并通过在方法上标注@Bean注解的方式注入bean。

Xml配置和Java类配置对比如下：

applicationContext-AppConfig.xml

<!-- 激活自动代理功能-->  
<aop:aspectj-autoproxy proxy-target-class="true" />  
     
<context:component-scan base-package="web.function">  
   <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>  
</context:component-scan>  
     
<import resource="classpath:config/context/applicationContext-CachingConfig.xml" />  
<import resource="classpath:config/context/applicationContext-DaoConfig.xml" />  

** ****AppConfig.java**

@Configuration  
@ComponentScan(basePackages = "web.function", excludeFilters = { @ComponentScan.Filter(type = FilterType.ANNOTATION, value = { Controller.class }) })  
@EnableAspectJAutoProxy(proxyTargetClass=true)  
@Import({CachingConfig.class,DaoConfig.class})  
public class AppConfig {  
}  

applicationContext-CachingConfig.xml

<!-- 启用缓存注解 -->  
<cache:annotation-driven cache-manager="cacheManager" />  
  
<!-- cacheManager工厂类，指定ehcache.xml的位置 -->  
<bean id="cacheManagerFactory"  
    class="org.springframework.cache.ehcache.EhCacheManagerFactoryBean"  
    p:configLocation="classpath:/config/ehcache.xml" />  
  
<!-- 声明cacheManager -->  
<bean id="cacheManager" class="org.springframework.cache.ehcache.EhCacheCacheManager"  
    p:cacheManager-ref="cacheManagerFactory" />  

**CachingConfig.java**** **

@Configuration  
@EnableCaching//<!-- 启用缓存注解 --> <cache:annotation-driven cache-manager="cacheManager" />  
public class CachingConfig {  
    private static final Logger logger = Logger.getLogger(CachingConfig.class);  
  
  
    @Bean  
    public EhCacheManagerFactoryBean ehCacheManagerFactoryBean() {  
        EhCacheManagerFactoryBean ehCacheManagerFactoryBean = new EhCacheManagerFactoryBean();  
        ehCacheManagerFactoryBean.setConfigLocation(new ClassPathResource(  
                "config/ehcache.xml"));  
        return ehCacheManagerFactoryBean;  
    }  
  
    @Bean  
    public CacheManager cacheManager() {  
        logger.info("EhCacheCacheManager");  
        EhCacheCacheManager cacheManager = new EhCacheCacheManager();  
        cacheManager.setCacheManager(ehCacheManagerFactoryBean().getObject());  
        return cacheManager;  
    }  
}  

applicationContext-DaoConfig.xml

<import resource="classpath:config/context/applicationContext-DataSourceConfig.xml" />  
 
     
   <bean id="sessionFactory"  
       class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">  
       <property name="dataSource" ref="dataSource" />  
       <property name="packagesToScan">  
           <list>  
               <value>web.function.**.model.oracle</value>  
           </list>  
       </property>  
       <property name="hibernateProperties">  
           <props>  
               <prop key="hibernate.dialect">  
                   ${hibernate.dialect}  
               </prop>  
               <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>  
               <prop key="hibernate.current_session_context_class">org.springframework.orm.hibernate4.SpringSessionContext</prop>  
           </props>  
       </property>  
   </bean>  
 
     
   <!-- hibernateDAO -->  
   <bean id="hibernateDAO" class="web.dao.hibernate.impl.CP_Hibernate4DAOImpl">  
     <property name="sessionFactory" ref="sessionFactory"></property>  
   </bean>  
       
     
   <bean id="transactionManager"  
       class="org.springframework.orm.hibernate4.HibernateTransactionManager">  
       <property name="sessionFactory" ref="sessionFactory" />  
   </bean>  
     
   <!-- 启用事务注解功能 -->  
   <tx:annotation-driven transaction-manager="transactionManager" />  

##**DaoConfig.java**

@Configuration
//启用注解事务管理，使用CGLib代理
@EnableTransactionManagement(proxyTargetClass = true)
@Import({DataSourceConfig.class})
public class DaoConfig {
private static final Logger logger = Logger.getLogger(DaoConfig.class);

@Value("${hibernate.dialect}")  
String hibernate_dialect;  
@Value("${hibernate.show_sql}")  
String hibernate_show_sql;  
  
/**                                                           
* 描述 : <负责解析资源文件>. <br>  
*<p>  
    <这个类必须有，而且必须声明为static，否则不能正常解析>   
 </p>                                                                                                                                                                                                                                                 
* @return                                                                                                       
*/    
@Bean  
public static PropertySourcesPlaceholderConfigurer placehodlerConfigurer() {  
    logger.info("PropertySourcesPlaceholderConfigurer");  
    return new PropertySourcesPlaceholderConfigurer();  
}  
  
@Resource(name="dataSource")  
public DataSource dataSource;  

  

@Bean(name = "sessionFactory")  
public LocalSessionFactoryBean localSessionFactoryBean() {  
    logger.info("sessionFactory");  
    LocalSessionFactoryBean sessionFactory = new LocalSessionFactoryBean();  
    sessionFactory.setDataSource(dataSource);  
    String[] packagesToScan = new String[] { "web.function.**.model.oracle" };  
    sessionFactory.setPackagesToScan(packagesToScan);  

    Properties hibernateProperties = new Properties();  
    hibernateProperties.setProperty("hibernate.dialect", hibernate_dialect);  
    hibernateProperties.setProperty("hibernate.show_sql",  
            hibernate_show_sql);  
    hibernateProperties.setProperty(  
            "hibernate.current_session_context_class",  
            "org.springframework.orm.hibernate4.SpringSessionContext");  
    sessionFactory.setHibernateProperties(hibernateProperties);  

    return sessionFactory;  

}  

@Bean(name = "hibernateDAO")  
public CP_Hibernate4DAOImpl hibernate4Dao() {  
    logger.info("hibernateDAO");  
    CP_Hibernate4DAOImpl dao = new CP_Hibernate4DAOImpl();  
    dao.setSessionFactory(localSessionFactoryBean().getObject());  
    return dao;  
}  

@Bean(name = "transactionManager")  
public HibernateTransactionManager hibernateTransactionManager() {  
    logger.info("transactionManager");  
    HibernateTransactionManager hibernateTransactionManager = new HibernateTransactionManager();  
    hibernateTransactionManager.setSessionFactory(localSessionFactoryBean()  
            .getObject());  
    return hibernateTransactionManager;  
}  

}

 
##**applicationContext-DataSourceConfig.xml**

<context:property-placeholder
location="classpath:/config/properties/db.properties" />

<!-- 数据源 -->  
<bean id="dataSource"  
    class="org.springframework.jdbc.datasource.DriverManagerDataSource">  
    <property name="driverClassName" value="${jdbc.driver}" />  
    <property name="url" value="${jdbc.url}" />  
    <property name="username" value="${jdbc.username}" />  
    <property name="password" value="${jdbc.password}" />  
</bean>  

 
##**DataSourceConfig.java**

@Configuration
//加载资源文件
@PropertySource({"classpath:/config/properties/db.properties"})
public class DataSourceConfig {
private static final Logger logger = Logger.getLogger(DataSourceConfig.class);
/*
* 绑定资源属性
*/
@Value("${jdbc.driver}")
String driverClass;
@Value("${jdbc.url}")
String url;
@Value("${jdbc.username}")
String userName;
@Value("${jdbc.password}")
String passWord;

@Bean(name = "dataSource")  
public DataSource dataSource() {  
    logger.info("DataSource");  
    DriverManagerDataSource dataSource = new DriverManagerDataSource();  
    dataSource.setDriverClassName(driverClass);  
    dataSource.setUrl(url);  
    dataSource.setUsername(userName);  
    dataSource.setPassword(passWord);  
    return dataSource;  
}  

}

 
##DataSource如果使用JNDI的方式如下：

<jee:jndi-lookup id="dataSource" jndi-name="jdbc/demoDB" />

##Java类配置：

@Bean
public JndiObjectFactoryBean jndiObjectFactoryBean(){
JndiObjectFactoryBean factory = new JndiObjectFactoryBean();
// factory.setJndiName("java:comp/env/jdbc/demoDB"); //两种方式均可，spring会自动补齐
factory.setJndiName("jdbc/demoDB");
return factory;
}

@Bean(name = "dataSource")  
public DataSource dataSource() throws Exception{  
    logger.info("DataSourceJNDI");  
    return (DataSource)jndiObjectFactoryBean().getObject();  
      
}