spring学习笔记（4）—— DI

spring学习笔记（4）—— DI

在配置文件中配置类和类的依赖关系

学生类

package com.test.code;

public class Student {
    private String name;
    private String id;

    private School school;

    public void studentDoing(){
        school.schoolDoing();
        System.out.println("这是个学生类");
    }

    public School getSchool() {
        return school;
    }

    public void setSchool(School school) {
        this.school = school;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }
}

学校类

package com.test.code;

public class School {
    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void schoolDoing(){
        System.out.println("这是个学校类");
    }
}

配置文件

语法

<bean id="名1" class="位置"/>
<bean id = "名2" class="位置">
<property name="类中属性名" ref="名1"/>
</bean>
名2类中有一属性是名1

名2类中有一属性是名1
property中name配置哪一个具体属性
property中ref属性参照的是哪一个bean

代码

<?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="school" class="com.test.code.School"/>
    <bean id = "student" class="com.test.code.Student">
        <property name="school" ref="school"/>
    </bean>

</beans>

效果