011.利用setter实现对象依赖注入

1.对象依赖注入

 

 2.利用setter实现静态数值的注入

2.1  pom.xml

       <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.2.6.RELEASE</version>
        </dependency>

2.2 resource目录下创建applicationContext.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
        https://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--Ioc容器自动利用反射机制运行时调用setXXXX方法自动为属性赋值-->
    <bean id="sweetApple" class="com.imooc.spring.ioc.entity.Apple">
        <property name="title" value="红富士"/>
        <property name="origin" value="欧洲"/>
        <property name="color" value="红色"/>
        <property name="price" value="5555.225"/>
    </bean>


</beans>

2.3 测试类

package com.imooc.spring.ioc;

import com.imooc.spring.ioc.entity.Apple;
import com.imooc.spring.ioc.entity.Child;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class SpringApplication
{
    public static void main(String[] args)
    {
        //创建SpringIoc容器，并根据配置文件在容器中实例化
        ApplicationContext context = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
        Apple sweetApple = context.getBean("sweetApple", Apple.class);
        System.out.println(sweetApple.getTitle());
     
    }
}

3. 利用setter方法实现对象注入

3.1 示例

 

 3.2  resource目录下创建applicationContext.xml               ref="sweetApple"

<?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
        https://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--Ioc容器自动利用反射机制运行时调用setXXXX方法自动为属性赋值-->
    <bean id="sweetApple" class="com.imooc.spring.ioc.entity.Apple">
        <property name="title" value="红富士"/>
        <property name="origin" value="欧洲"/>
        <property name="color" value="红色"/>
        <property name="price" value="5555.225"/>
    </bean>

    <bean id="lily" class="com.imooc.spring.ioc.entity.Child">
        <property name="name" value="lili"/>
        <!--利用ref注入依赖对象-->
        <property name="apple" ref="sweetApple"/>
    </bean>


</beans>