主题：Buffalo与Spring也能玩转annotation
转自： http://www.iteye.com/topic/255397
1.那即将离我远去的
用buffalo作为我的ajax类库也有些历史了,几乎是和Spring同时开始接触的.
按照官方的方式,Buffalo与Spring的集成是很简单:
在Spring中配置一个BuffaloServiceConfigure bean,把spring托管的服务在其中声明即可,Buffalo可以通过ServletContext得到Spring的WebApplicationContext,进而得到所需的服务:
Java代码
- <bean name="buffaloConfigBean"
- class="net.buffalo.service.BuffaloServiceConfigurer">
- <property name="services">
- <map>
- <entry key="springSimpleService">
- <ref bean="systemService" />
- </entry>
- <entry key="springSimpleService2">
- <ref bean="systemService2" />
- </entry>
- </map>
- </property>
- </bean>
<bean name="buffaloConfigBean"
class="net.buffalo.service.BuffaloServiceConfigurer">
<property name="services">
<map>
<entry key="springSimpleService">
<ref bean="systemService" />
</entry>
<entry key="springSimpleService2">
<ref bean="systemService2" />
</entry>
</map>
</property>
</bean>
似乎很简单,但,有没有觉得似乎很傻?只是把Spring里已经配置好的bean再引用一次而已,
一旦面临协作开发,和所有的全局配置文件一样,BuffaloServiceConfigure bean下面就会囊括几十上百个service ref,一大堆人围着这个配置文件转,CVS冲突就成了家常便饭了,苦恼不已.当然,按我们这么多年的开发经验是不会出现这种低级错误的,早早的在项目设计阶段就会按模块划分出多个配置文件,一人独用,无需和别人共享配置,轻松面对冲突问题,带来的局面就是每个包里都塞着一个buffalo.xml,一个项目里配置文件到处有,不断得copy/paste,层层套套,那可不是硕果累累的满足感.
当然,Spring本身在2.5之前也因XML配置繁琐而让人诟病,Guice才能异军突起,那时Spring比Buffalo的配置更多,所以Buffalo的问题也就不是问题了.但有一天,我终于要正式升级到Spring2.5.
世界清静了!使用annotation,看到怎么多配置文件消失,看到简洁的Bean/MVC配置,呵呵,还真是令人心情愉悦的.
诶,等等,怎么还有大堆XML?哦?原来是Buffalo...
Buffalo像个刺头,傻愣愣地杵在XML里.
2.于是我开始把Buffalo也Annotation化.
话说Spring的扩展能力还是ganggang的,一天时间,就有成果了.
先写个注解:
Java代码
- package cn.tohot.common.annotation;
- import java.lang.annotation.ElementType;
- import java.lang.annotation.Retention;
- import java.lang.annotation.RetentionPolicy;
- import java.lang.annotation.Target;
- /**
- * buffalo扩展接口,用于表明该类是一个buffalo服务.
- * @author tedeyang
- *
- */
- @Retention(RetentionPolicy.RUNTIME)
- @Target(ElementType.TYPE)
- public @interface Buffalo {
- /**
- * @return 远程调用时的服务名.
- */
- String value();
- }
package cn.tohot.common.annotation;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* buffalo扩展接口,用于表明该类是一个buffalo服务.
* @author tedeyang
*
*/
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
public @interface Buffalo {
/**
* @return 远程调用时的服务名.
*/
String value();
}
接着再写Spring的扩展
Java代码
- /**
- *
- */
- package cn.tohot.common.annotation;
- import java.util.HashMap;
- import net.buffalo.service.BuffaloServiceConfigurer;
- import org.apache.log4j.Logger;
- import org.springframework.beans.BeansException;
- import org.springframework.beans.factory.DisposableBean;
- import org.springframework.beans.factory.FactoryBean;
- import org.springframework.beans.factory.InitializingBean;
- import org.springframework.beans.factory.config.BeanPostProcessor;
- /**
- * 该类作为FactoryBean可以无缝替换buffalo 2.0自带的配置类,并使用annotation进行配置.
- * @author tedeyang
- *
- */
- @SuppressWarnings("unchecked")
- public class BuffaloAnnotationServiceFactoryBean implements FactoryBean, InitializingBean, DisposableBean, BeanPostProcessor {
- private static final Logger log = Logger.getLogger(BuffaloAnnotationServiceFactoryBean.class);
- private BuffaloServiceConfigurer buffaloConfigurer = null;
- public BuffaloAnnotationServiceFactoryBean() {
- buffaloConfigurer = new BuffaloServiceConfigurer();
- buffaloConfigurer.setServices(new HashMap());
- }
- private void addBuffaloBean(String buffaloServiceName,Object bean) {
- buffaloConfigurer.getServices().put(buffaloServiceName, bean);
- log.info("Add a buffalo service :"+buffaloServiceName);
- }
- public Object getObject() throws Exception {
- return this.buffaloConfigurer;
- }
- public Class getObjectType() {
- return BuffaloServiceConfigurer.class;
- }
- public boolean isSingleton() {
- return true;
- }
- public void afterPropertiesSet() throws Exception {
- }
- public void destroy() throws Exception {
- if (buffaloConfigurer != null)
- buffaloConfigurer.setServices(null);
- buffaloConfigurer = null;
- }
- public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
- return bean;
- }
- public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
- log.debug("find a bean:"+beanName);
- if (bean.getClass().isAnnotationPresent(Buffalo.class)) {
- Buffalo buffalo = bean.getClass().getAnnotation(Buffalo.class);
- addBuffaloBean(buffalo.value(), bean);
- }
- return bean;
- }
- }
/**
*
*/
package cn.tohot.common.annotation;
import java.util.HashMap;
import net.buffalo.service.BuffaloServiceConfigurer;
import org.apache.log4j.Logger;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.config.BeanPostProcessor;
/**
* 该类作为FactoryBean可以无缝替换buffalo 2.0自带的配置类,并使用annotation进行配置.
* @author tedeyang
*
*/
@SuppressWarnings("unchecked")
public class BuffaloAnnotationServiceFactoryBean implements FactoryBean, InitializingBean, DisposableBean, BeanPostProcessor {
private static final Logger log = Logger.getLogger(BuffaloAnnotationServiceFactoryBean.class);
private BuffaloServiceConfigurer buffaloConfigurer = null;
public BuffaloAnnotationServiceFactoryBean() {
buffaloConfigurer = new BuffaloServiceConfigurer();
buffaloConfigurer.setServices(new HashMap());
}
private void addBuffaloBean(String buffaloServiceName,Object bean) {
buffaloConfigurer.getServices().put(buffaloServiceName, bean);
log.info("Add a buffalo service :"+buffaloServiceName);
}
public Object getObject() throws Exception {
return this.buffaloConfigurer;
}
public Class getObjectType() {
return BuffaloServiceConfigurer.class;
}
public boolean isSingleton() {
return true;
}
public void afterPropertiesSet() throws Exception {
}
public void destroy() throws Exception {
if (buffaloConfigurer != null)
buffaloConfigurer.setServices(null);
buffaloConfigurer = null;
}
public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
return bean;
}
public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
log.debug("find a bean:"+beanName);
if (bean.getClass().isAnnotationPresent(Buffalo.class)) {
Buffalo buffalo = bean.getClass().getAnnotation(Buffalo.class);
addBuffaloBean(buffalo.value(), bean);
}
return bean;
}
}
主要思路是用FactoryBean替换原BuffaloServiceConfigurer,并挂上BeanPostProcessor的钩子,检测一下annotation,发现buffalo服务就添加到原BuffaloServiceConfigurer中去.
3.今天我这样配置Buffalo:
Java代码
- <?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">
- <!-- Spring Annotation配置, 自动搜索组件 -->
- <context:component-scan base-package="cn.tohot.demo"/>
- <bean id="buffalo" class="cn.tohot.common.annotation.BuffaloAnnotationServiceFactoryBean" />
- </beans>
<?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">
<!-- Spring Annotation配置, 自动搜索组件 -->
<context:component-scan base-package="cn.tohot.demo"/>
<bean id="buffalo" class="cn.tohot.common.annotation.BuffaloAnnotationServiceFactoryBean" />
</beans>
服务端的Buffalo bean 类:
Java代码
- package cn.tohot.demo;
- import org.springframework.stereotype.Service;
- import cn.tohot.common.annotation.Buffalo;
- @Service //声明Spring bean,
- @Buffalo("testbean") //声明一个名为"testbean"的Buffalo service
- public class BuffaloBeanTestService {
- public String run() {
- System.out.println("run");
- return "run";
- }
- }
package cn.tohot.demo;
import org.springframework.stereotype.Service;
import cn.tohot.common.annotation.Buffalo;
@Service //声明Spring bean,
@Buffalo("testbean") //声明一个名为"testbean"的Buffalo service
public class BuffaloBeanTestService {
public String run() {
System.out.println("run");
return "run";
}
}
很简洁,不是吗?