SPRING IN ACTION 第4版笔记-第一章-002-DI介绍

一、

1.knight.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://www.springframework.org/schema/beans 
      http://www.springframework.org/schema/beans/spring-beans.xsd">

  <bean id="knight" class="chapter01.sia.knights.BraveKnight">
    <constructor-arg ref="quest" />
  </bean>

  <bean id="quest" class="chapter01.sia.knights.SlayDragonQuest">
    <constructor-arg value="#{T(System).out}" />
  </bean>

</beans>

2.Knight

package chapter01.sia.knights;

public interface Knight {

  void embarkOnQuest();

}

3.BraveKnight

package chapter01.sia.knights;
  
public class BraveKnight implements Knight {

  private Quest quest;

  public BraveKnight(Quest quest) {
    this.quest = quest;
  }

  public void embarkOnQuest() {
    quest.embark();
  }

}

4.SlayDragonQuest

package chapter01.sia.knights;

import java.io.PrintStream;

public class SlayDragonQuest implements Quest {

  private PrintStream stream;

  public SlayDragonQuest(PrintStream stream) {
    this.stream = stream;
  }

  public void embark() {
    stream.println("Embarking on quest to slay the dragon!");
  }

}

5.

package chapter01.sia.knights;

import org.springframework.context.support.
                   ClassPathXmlApplicationContext;

public class KnightMain {

  public static void main(String[] args) throws Exception {
    ClassPathXmlApplicationContext context = 
        new ClassPathXmlApplicationContext("classpath:knight.xml");
    Knight knight = context.getBean(Knight.class);
    knight.embarkOnQuest();
    context.close();
  }

}

6.运行

三月 01, 2016 9:42:47 上午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@4ec12ad8: startup date [Tue Mar 01 09:42:47 CST 2016]; root of context hierarchy
三月 01, 2016 9:42:47 上午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [knight.xml]
三月 01, 2016 9:42:47 上午 org.springframework.context.support.ClassPathXmlApplicationContext doClose
信息: Closing org.springframework.context.support.ClassPathXmlApplicationContext@4ec12ad8: startup date [Tue Mar 01 09:42:47 CST 2016]; root of context hierarchy
Embarking on quest to slay the dragon!