IOC的兩種方式：

• XML方式
• 註解方式

XML方式

需要的jar包

spring-beans-4.3.3.RELEASE.jar

spring-context-4.3.3.RELEASE.jar

spring-context-support-4.3.3.RELEASE.jar

spring-core-4.3.3.RELEASE.jar

spring-expression-4.3.3.RELEASE.jar

1. 建立 applicationContext.xml配置檔案

<?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">
 
</beans>
 

2. 在beans目錄中增加要初始化的javaBean（bean標籤）

<?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">

 
    <!--建立物件kazhafei-->
    <bean id="kazhafei" class="org.spring.example.Kazhafei" />
</beans>
 

3.開始測試

package org.spring.example;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.context.support.FileSystemXmlApplicationContext;

public class Test { 
    public static void main(String[] args) { 
        //初始化Spring IOC容器 ClassPathXmlApplicationContext:類路徑方式  推薦
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");

        System.out.println("-----------------IOC初始化完畢-------------------");
        //獲取Bean物件
        People people1 = (People) applicationContext.getBean("kazhafei");
        people1.getPeopleName();
    }
}
 

初始化SpringIOC容器的時候就會初始化好javaBean

從SpringIOC容器中獲取物件時，不會再執行構造方法（預設單例）