day118 - 基于xml管理bean的入门案例

<dependencies>
    <!-- 基于Maven依赖传递性，导入spring-context依赖即可导入当前所需所有jar包 -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>5.3.1</version>
    </dependency>
    <!-- junit测试 -->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
        <scope>test</scope>
    </dependency>
</dependencies>

package com.gu.spring.pojo;
​
public class HelloWorld {
    public void sayHello(){
        System.out.println("hello spring");
    }
}

<!--
    bean: 将对象交给ioc容器管理
    属性：
    id：bean得唯一标识，不能重复
    class：设置bean对象所对应的类型
-->
    <bean id="helloworld" class="com.gu.spring.pojo.HelloWorld"></bean>

@Test
public void test(){
    //获取ioc容器
    ApplicationContext ioc = new ClassPathXmlApplicationContext("applicationContext.xml");
    //获取ioc容器中的bean对象
    HelloWorld helloworld = (HelloWorld) ioc.getBean("helloworld");
    helloworld.sayHello();
​
}