以上笔记来源：
尚硅谷Spring零基础入门到进阶，一套搞定spring6全套视频教程（源码级讲解）https://www.bilibili.com/video/BV1kR4y1b7Qc
13 依赖注入之引入集合Bean属性
13.1 创建Lesson类，student类和teacher实体类
由于1个学生对于多个课程，因此在学生实体类中创建lessonList的集合变量，并且在学生实体类中创建教师Map集合变量
package com.atguigu.spring6.iocxml.dimap;
/**
* @package: com.atguigu.spring6.iocxml.dimap
* @className: Lesson
* @Description:
* @author: haozihua
* @date: 2024/9/26 14:39
*/
public class Lesson {
private String lessonName;
public String getLessonName() {
return lessonName;
}
public void setLessonName(String lessonName) {
this.lessonName = lessonName;
}
@Override
public String toString() {
return "Lesson{" +
"lessonName='" + lessonName + '\'' +
'}';
}
}package com.atguigu.spring6.iocxml.dimap;
import java.util.List;
import java.util.Map;
/**
* @package: com.atguigu.spring6.iocxml.dimap
* @className: Student
* @Description:
* @author: haozihua
* @date: 2024/8/20 15:20
*/
public class Student {
private List<Lesson> lessonList;
//一个学生对应很多个老师
private Map<String,Teacher> teacherMap;
private String sid;
private String sname;
public List<Lesson> getLessonList() {
return lessonList;
}
public void setLessonList(List<Lesson> lessonList) {
this.lessonList = lessonList;
}
public String getSid() {
return sid;
}
public void setSid(String sid) {
this.sid = sid;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public Map<String, Teacher> getTeacherMap() {
return teacherMap;
}
public void setTeacherMap(Map<String, Teacher> teacherMap) {
this.teacherMap = teacherMap;
}
public void run() {
System.out.println("学生编号： " + sid + " " + "学生名称：" + sname);
System.out.println(teacherMap);
for (String teacher : teacherMap.keySet()) {
System.out.println(teacher);
}
for (Teacher teacher : teacherMap.values()) {
System.out.println(teacher);
}
}
}package com.atguigu.spring6.iocxml.dimap;
/**
* @package: com.atguigu.spring6.iocxml.dimap
* @className: Teacher
* @Description:
* @author: haozihua
* @date: 2024/8/20 15:21
*/
public class Teacher {
private Integer teacherId;
private String teacherName;
public Integer getTeacherId() {
return teacherId;
}
public void setTeacherId(Integer teacherId) {
this.teacherId = teacherId;
}
public String getTeacherName() {
return teacherName;
}
public void setTeacherName(String teacherName) {
this.teacherName = teacherName;
}
@Override
public String toString() {
return "Teacher{" +
"teacherId=" + teacherId +
", teacherName='" + teacherName + '\'' +
'}';
}
public Teacher(Integer teacherId, String teacherName) {
this.teacherId = teacherId;
this.teacherName = teacherName;
}
public Teacher() {
}
}13.2 创建XML配置文件
在使用util:list以及util:map标签时，首先必须对头部约束文件进行设置，覆盖约束内容如下：
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/util
http://www.springframework.org/schema/util/spring-util.xsd
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">之后，可以将Property属性中name属性以及<list>,<map>标签转换为util:list以及util:map标签，从而简化注入流程。
之后将util:list>id>ref bean标签以及util:map>id>entry>key>value或者key>ref设置好
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/util
http://www.springframework.org/schema/util/spring-util.xsd
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">
<!--
1.创建三个对象
2.注入普通类型属性
3.使用util:类型 定义
4.在学生bean引入util:类型定义bean，完成list，map类型的注入-->
<bean id="student" class="com.atguigu.spring6.iocxml.dimap.Student">
<property name="sid" value="10000"></property>
<property name="sname" value="lucy"></property>
<property name="lessonList" ref="lessonList"></property>
<property name="teacherMap" ref="teacherMap"></property>
</bean>
<util:list id="lessonList">
<ref bean="lessonone"></ref>
<ref bean="lessontwo"></ref>
</util:list>
<util:map id="teacherMap">
<entry>
<key>
<value>10010</value>
</key>
<ref bean="teacherone"></ref>
</entry>
<entry>
<key>
<value>10011</value>
</key>
<ref bean="teachertwo"></ref>
</entry>
</util:map>
<bean id="lessonone" class="com.atguigu.spring6.iocxml.dimap.Lesson">
<property name="lessonName" value="java开发"></property>
</bean>
<bean id="lessontwo" class="com.atguigu.spring6.iocxml.dimap.Lesson">
<property name="lessonName" value="python开发"></property>
</bean>
<bean id="teacherone" class="com.atguigu.spring6.iocxml.dimap.Teacher">
<property name="teacherId" value="101"></property>
<property name="teacherName" value="贾宝玉"></property>
</bean>
<bean id="teachertwo" class="com.atguigu.spring6.iocxml.dimap.Teacher">
<property name="teacherId" value="102"></property>
<property name="teacherName" value="李时珍"></property>
</bean>
</beans>13.3 运行测试类方法
@Test
public void Testp(){
ApplicationContext context =
new ClassPathXmlApplicationContext("bean-diref.xml");
Student student = context.getBean("student",Student.class);
student.run();
}13.4 运行结果如图所示
