Spring 2.5新特性――使用注解方式的Ioc

ApplicationContext.xml配置

<?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: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/context
       http://www.springframework.org/schema/context/spring-context-2.5.xsd" default-lazy-init="true">
          
    <context:annotation-config />
    <context:component-scan base-package="com.xued.techevaluate.ioc,com.xued.techevaluate" />
   
</beans>

除了要注入一些外部资源，基本上不再需要配置<bean/>项。

两个bean的代码，实现同一个接口

@Component(value="Bloomberg")
public class BloombergDataService implements MarketDataService{

    @PostConstruct
    private void init(){
        System.out.println ("Bloomberg service initiallized");
    }
       
    public String getStockData(String stockCode) {
        StringBuilder sb = new StringBuilder();
        sb.append("/*************************************************************\n" +
                       "*             Bloomberg market Data Provider                 *\n" +
                       "*************************************************************/\n");
        sb.append("StockCode      Company      Price      Amount      Time      ");
        sb.append("\n");
        sb.append(stockCode + "      长江实业      136.60      200000      "+ new Date());
        return sb.toString();
    }

}

@Component(value="Reuters")
public class ReutersDataService implements MarketDataService{

    @PostConstruct
    private void init(){
        System.out.println("Reuters service initiallized");
    }
   
    public String getStockData(String stockCode) {
        StringBuilder sb = new StringBuilder();
        sb.append("/*************************************************************\n" +
                       "*             Reuters market Data Provider                   *\n" +
                       "*************************************************************/\n");
        sb.append("StockCode      Company      Price      Amount      Time      ");
        sb.append ("\n");
        sb.append(stockCode + "      长江实业      136.60      200000      "+ new Date());
        return sb.toString();
    }

}

注入的代码：

@Component(value="dataMiner")
public class DataMiner {

    @Resource(name="Reuters")
    private MarketDataService dataService;

    public String queryByCode(String stockCode){
        return dataService.getStockData(stockCode);
    }
}

采用传统方式取得bean引用：

        ApplicationContext ctx = new ClassPathXmlApplicationContext("ApplicationContext.xml");
        instance = (DataMiner)ctx.getBean("dataMiner");