Spring IOC学习(2) +xml文件配置相关

xml配置默认使用类的无参构造

当类存在有参构造函数时

package Test;

public class Hello {
    private String name;
    public Hello(){
        System.out.println("Hello对象被创建");
    }
    public Hello(String name){
        this.name=name;
    }
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
    public void show(){
        System.out.println("name="+name);
    }
}

xml配置文件:

<?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">
    <bean id="hello" class="Test.Hello">
        <!--index为参数的下标 从0开始-->
        <constructor-arg index="0" value="jie"/>
    </bean>
</beans>

官方文档: