Jacally

上一篇“Flex 开发学习笔记1 - 与Flex的亲密接触,秀一下两周的成果”

       上篇中show了一下近期作的demo页面，现在讲一讲我使用的架构：

       自己原来的项目架构是 WebWork2 + Spring + Hibernate，现在通过FLex替代了WebWrok2来表显视图层，而Flex与Spring通讯采用了BlazeDS这个开源免费的Flex服务程序。

       BlazeDS是Adobe公司发布的免费开源产品，与该公司的另一款收费产品LCDS功能相近，应该是LCDS简化开源免费版。目前我通过RemoteObject的方式访问后台Service感觉比较方便。BlazeDS下载地址：http://opensource.adobe.com/wiki/display/blazeds/download+blazeds+3

       如何通过RemoteObject访问Spring管理的Bean，我参照另一篇教程文档进行了设计与开发，在这篇文章中，用的是Adobe非免费Flex服务程序，只需要将LCDS中的flex.war换成BlazeDS中的flex.war就可以了。另外，这里有一篇“使用BlazeDS实现Java和Flex通信 ”的文章，讲解了如何在eclipse中配置Flex工程。

       以下是一个Flex页面访问RemoteObject的代码：

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
	<mx:Script>
		<![CDATA[
			import mx.rpc.events.ResultEvent;
			import mx.controls.Alert;
			private function callRO(str:String):void{
				Alert.show("flexSpringBeanTest");
				firstRO.say(str);
				firstRO.addEventListener(ResultEvent.RESULT,getROResult);
			}
			
			private function getROResult(e:ResultEvent) :void {
				Alert.show(e.result.toString());
			}
			//flexObjectTest
		]]>
	</mx:Script>
	
	<mx:RemoteObject id="firstRO" destination="flexSpringBeanTest"/>
	<mx:TextInput x="109" y="28" id="input" text="hello!"/>
	<mx:Button x="270" y="28" click="callRO(input.text)" label="请求"/>
</mx:Application>

   在remote-config.xml配置里，映射一个Spring管理的Bean是这么写的

  <destination id="flexSpringBeanTest">
        <properties>
                <factory>springFactory</factory> 
                <source>flexObjectTest</source>
        </properties>
  </destination>

    在services-config.xml配置自定义的SpringFactory类,即我们要实现从从spring容器中去取得bean。

  <factories>
        <factory id="springFactory" class="cn.org.coral.core.flex.factory.FlexSpringFactory" /> 
  </factories>

    这个工厂类的定义:

package cn.org.coral.core.flex.factory;

import flex.messaging.FactoryInstance;
import flex.messaging.FlexFactory;
import flex.messaging.config.ConfigMap;

/**
 * 要对某个java类实现自己定义的切入，可以使用工厂配置，需要在ro访问前，从spring里去getbean<br>
 * 
 * @author Libin
 *
 */
public class FlexSpringFactory implements FlexFactory{

	@Override
	public FactoryInstance createFactoryInstance(String id, ConfigMap properties){
        SpringFactoryInstance instance = new SpringFactoryInstance(this, id, properties);
        instance.setSource(properties.getPropertyAsString(SOURCE, instance.getId()));
        return instance;
    }
	@Override
	public Object lookup(FactoryInstance inst)  {
        SpringFactoryInstance factoryInstance = (SpringFactoryInstance) inst;
        return factoryInstance.lookup();
    } 

	@Override
	public void initialize(String arg0, ConfigMap arg1) {
		// TODO Auto-generated method stub
		
	}

}

该factory需要实现FlexFactory接口。实现createFactoryInstance方法和lookup方法

package cn.org.coral.core.flex.factory;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.context.ApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;

import flex.messaging.FactoryInstance;
import flex.messaging.config.ConfigMap;
import flex.messaging.services.ServiceException;

public class SpringFactoryInstance extends FactoryInstance
{
    SpringFactoryInstance(FlexSpringFactory factory, String id, ConfigMap properties)
    {
        super(factory, id, properties);
    }
    public Object lookup() 
    {
        //这就是从spring容器中getbean了
        ApplicationContext appContext = WebApplicationContextUtils.getWebApplicationContext(flex.messaging.FlexContext.getServletConfig().getServletContext());
        String beanName = getSource();

        try
        {
            return appContext.getBean(beanName);
        }
        catch (NoSuchBeanDefinitionException nexc)
        {
            ServiceException e = new ServiceException();
            throw e;
        }
        catch (BeansException bexc)
        {
            ServiceException e = new ServiceException();
            throw e;
        } 
    }
    
} 

   后台service的定义：

package cn.org.coral.sample.flex.manager;

public class FlexObjectTest {

	public String say(String str){
		return "say : " + str;
	}
	
}

  spring-context.xml的配置

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>

	<bean id="flexObjectTest"
		class="cn.org.coral.sample.flex.manager.FlexObjectTest">
	</bean>

</beans>