spring揭秘 读书笔记 一

标签：spring   读书笔记   ioc   

本文是王福强所著<<spring揭秘>>一书的读书笔记

ioc的基本概念

一个例子

public class FXNewsProvider  
{ 


  private IFXNewsListener  newsListener; 
  private IFXNewsPersister newPersistener; 
  
    public void getAndPersistNews() { 
     String[] newsIds = newsListener.getAvailableNewsIds(); 
     if(ArrayUtils.isEmpty(newsIds)) { 
	  return; 
     }     
   
   for(String newsId : newsIds) { 
     FXNewsBean newsBean = newsListener.getNewsByPK(newsId); 
     newPersistener.persistNews(newsBean); 
     newsListener.postProcessIfNecessary(newsId); 
    }
    
  } 
}  

public FXNewsProvider()  { 
  newsListener   = new DowJonesNewsListener(); 
  newPersistener = new DowJonesNewsPersister(); 
}  

public FXNewsProvider(IFXNewsListener newsListner,IFXNewsPersister newsPersister)  { 
  this.newsListener   = newsListner; 
  this.newPersistener = newsPersister; 
}

//使用DowJones家的新闻
FXNewsProvider dowJonesNewsProvider =
new FXNewsProvider(new DowJonesNewsListener(),new DowJonesNewsPersister()); 
//MarketWin24家的新闻
FXNewsPrivider marketWin24NewsProvider = 
new FXNewsProvider(new MarketWin24NewsListener(),new DowJonesNewsPersister()); 

注入方式

public class FXNewsProvider  { 
  private IFXNewsListener  newsListener; 
  private IFXNewsPersister newPersistener; 
  
  public IFXNewsListener getNewsListener() { 
   return newsListener; 
  } 
  public void setNewsListener(IFXNewsListener newsListener) { 
   this.newsListener = newsListener; 
  } 
  public IFXNewsPersister getNewPersistener() { 
   return newPersistener; 
  } 
  public void setNewPersistener(IFXNewsPersister newPersistener) { 
   this.newPersistener = newPersistener; 
  } 
} 

掌管大局的IoC Service Provider

IFXNewsListener newsListener = new DowJonesNewsListener(); 
IFXNewsPersister newsPersister = new DowJonesNewsPersister(); 
FXNewsProvider newsProvider = new FXNewsProvider(newsListener,newsPersister); 
newsProvider.getAndPersistNews();  

IoC Service Provider的职责

如何管理依赖关系

硬编码

IoContainer container = ...; 
container.register(FXNewsProvider.class,new FXNewsProvider()); 
container.register(IFXNewsListener.class,new DowJonesNewsListener()); 
container.register(IFXNewsPersister.class,new DowJonesNewsPersister()); 


//setRelation这个方法是我自己写的 sping不会这么干的 但是大概能说明问题
container.setRelation(FXNewsProvider.class,newsListener,IFXNewsListener.class);
container.setRelation(FXNewsProvider.class,newPersistener,IFXNewsPersister.class);


FXNewsProvider newsProvider = (FXNewsProvider)container.get(FXNewsProvider.class); 
newProvider.getAndPersistNews(); 

public static void main(String[] args)  {  
  DefaultListableBeanFactory beanRegistry = new DefaultListableBeanFactory(); 
  BeanFactory container = (BeanFactory)bindViaCode(beanRegistry); 
  FXNewsProvider newsProvider = 
  (FXNewsProvider)container.getBean("djNewsProvider"); 
  newsProvider.getAndPersistNews(); 
} 
 
public static BeanFactory bindViaCode(BeanDefinitionRegistry registry) { 
    AbstractBeanDefinition newsProvider = 
    new RootBeanDefinition(FXNewsProvider.class,true); 
    AbstractBeanDefinition newsListener = 
    new RootBeanDefinition(DowJonesNewsListener.class,true); 
    AbstractBeanDefinition newsPersister = 
    new RootBeanDefinition(DowJonesNewsPersister.class,true); 


    // 将bean定义注册到容器中 
    registry.registerBeanDefinition("djNewsProvider", newsProvider); 
    registry.registerBeanDefinition("djListener", newsListener); 
    registry.registerBeanDefinition("djPersister", newsPersister); 


    // 指定依赖关系 
    // 1. 可以通过构造方法注入方式 
    ConstructorArgumentValues argValues = new ConstructorArgumentValues(); 
    argValues.addIndexedArgumentValue(0, newsListener); 
    argValues.addIndexedArgumentValue(1, newsPersister); 
    newsProvider.setConstructorArgumentValues(argValues); 
  
    // 2. 或者通过setter方法注入方式 
    MutablePropertyValues propertyValues = new MutablePropertyValues(); 
    propertyValues.addPropertyValue(new ropertyValue("newsListener",newsListener)); 
    propertyValues.addPropertyValue(new PropertyValue("newPersistener",newsPersister)); 
    newsProvider.setPropertyValues(propertyValues); 
    // 绑定完成      
    return (BeanFactory)registry; 
}  

配置文件方式

<bean id="newsProvider" class="..FXNewsProvider"> 
  <property name="newsListener"> 
   <ref bean="djNewsListener"/> 
  </property> 
  <property name="newPersistener"> 
   <ref bean="djNewsPersister"/> 
  </property> 
</bean> 
 
<bean id="djNewsListener"  
  class="..impl.DowJonesNewsListener"> 
</bean> 
<bean id="djNewsPersister"  
  class="..impl.DowJonesNewsPersister"> 
</bean>  

... 
container.readConfigurationFiles(...); 
FXNewsProvider newsProvider = (FXNewsProvider)container.getBean("newsProvider"); 
newsProvider.getAndPersistNews(); 

元数据方式(注解方式)

public class FXNewsProvider  {   
  private IFXNewsListener  newsListener; 
  private IFXNewsPersister newPersistener; 


  @Inject 
  public FXNewsProvider(IFXNewsListener listener,IFXNewsPersister persister)    { 
    this.newsListener   = listener; 
    this.newPersistener = persister; 
  } 


}  

 public class NewsBindingModule extends AbstractModule  { 


  @Override 
  protected void configure() { 
   bind(IFXNewsListener.class).to(DowJonesNewsListener.class).in(Scopes.SINGLETON); 
   bind(IFXNewsPersister.class).to(DowJonesNewsPersister.class).in(Scopes.SINGLETON); 
  } 


}  

Injector injector = Guice.createInjector(new NewsBindingModule()); 
FXNewsProvider newsProvider = injector.getInstance(FXNewsProvider.class); 
newsProvider.getAndPersistNews(); 

spring揭秘 读书笔记 一

标签：spring   读书笔记   ioc   

原文地址：http://blog.csdn.net/dlf123321/article/details/47813985