Spring之容器：IOC（2）

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前言

7、实验六：为数组类型属性赋值
8、实验七：为集合类型属性赋值
①为List集合类型属性赋值
②为Map集合类型属性赋值
③引用集合类型的bean
9、实验八：p命名空间
10、实验九：引入外部属性文件
7、实验六：为数组类型属性赋值
8、实验七：为集合类型属性赋值
①为List集合类型属性赋值
②为Map集合类型属性赋值
③引用集合类型的bean
9、实验八：p命名空间
10、实验九：引入外部属性文件

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7、实验六：为数组类型属性赋值

①修改Student类

在Student类中添加以下代码：

private String[] hobbies;

public String[] getHobbies() {
    return hobbies;
}

public void setHobbies(String[] hobbies) {
    this.hobbies = hobbies;
}

②配置bean

<bean id="studentFour" class="com.gedeshidai.spring.bean6.Student">
    <property name="id" value="1004">property>
    <property name="name" value="赵六">property>
    <property name="age" value="26">property>
    <property name="sex" value="女">property>
    
    <property name="clazz" ref="clazzOne">property>
    <property name="hobbies">
        <array>
            <value>抽烟value>
            <value>喝酒value>
            <value>烫头value>
        array>
    property>
bean>

8、实验七：为集合类型属性赋值

①为List集合类型属性赋值

在Clazz类中添加以下代码：

private List<Student> students;

public List<Student> getStudents() {
    return students;
}

public void setStudents(List<Student> students) {
    this.students = students;
}

配置bean：

<bean id="clazzTwo" class="com.gedeshidai.spring6.bean.Clazz">
    <property name="clazzId" value="4444">property>
    <property name="clazzName" value="Javaee0222">property>
    <property name="students">
        <list>
            <ref bean="studentOne">ref>
            <ref bean="studentTwo">ref>
            <ref bean="studentThree">ref>
        list>
    property>
bean>

若为Set集合类型属性赋值，只需要将其中的list标签改为set标签即可

②为Map集合类型属性赋值

创建教师类Teacher：

package com.gedeshidai.spring6.bean;
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;
    }

    public Teacher(Integer teacherId, String teacherName) {
        this.teacherId = teacherId;
        this.teacherName = teacherName;
    }

    public Teacher() {

    }
    
    @Override
    public String toString() {
        return "Teacher{" +
                "teacherId=" + teacherId +
                ", teacherName='" + teacherName + '\'' +
                '}';
    }
}

在Student类中添加以下代码：

private Map<String, Teacher> teacherMap;

public Map<String, Teacher> getTeacherMap() {
    return teacherMap;
}

public void setTeacherMap(Map<String, Teacher> teacherMap) {
    this.teacherMap = teacherMap;
}

配置bean：

<bean id="teacherOne" class="com.atguigu.spring6.bean.Teacher">
    <property name="teacherId" value="10010">property>
    <property name="teacherName" value="大宝">property>
bean>

<bean id="teacherTwo" class="com.gedeshidaia.spring6.bean.Teacher">
    <property name="teacherId" value="10086">property>
    <property name="teacherName" value="二宝">property>
bean>

<bean id="studentFour" class="com.atguigu.spring6.bean.Student">
    <property name="id" value="1004">property>
    <property name="name" value="赵六">property>
    <property name="age" value="26">property>
    <property name="sex" value="女">property>
    
    <property name="clazz" ref="clazzOne">property>
    <property name="hobbies">
        <array>
            <value>抽烟value>
            <value>喝酒value>
            <value>烫头value>
        array>
    property>
    <property name="teacherMap">
        <map>
            <entry>
                <key>
                    <value>10010value>
                key>
                <ref bean="teacherOne">ref>
            entry>
            <entry>
                <key>
                    <value>10086value>
                key>
                <ref bean="teacherTwo">ref>
            entry>
        map>
    property>
bean>

③引用集合类型的bean

<util:list id="students">
    <ref bean="studentOne">ref>
    <ref bean="studentTwo">ref>
    <ref bean="studentThree">ref>
util:list>

<util:map id="teacherMap">
    <entry>
        <key>
            <value>10010value>
        key>
        <ref bean="teacherOne">ref>
    entry>
    <entry>
        <key>
            <value>10086value>
        key>
        <ref bean="teacherTwo">ref>
    entry>
util:map>
<bean id="clazzTwo" class="com.atguigugu.spring6.bean.Clazz">
    <property name="clazzId" value="4444">property>
    <property name="clazzName" value="Javaee0222">property>
    <property name="students" ref="students">property>
bean>
<bean id="studentFour" class="com.gedeshidai.spring6.bean.Student">
    <property name="id" value="1004">property>
    <property name="name" value="赵六">property>
    <property name="age" value="26">property>
    <property name="sex" value="女">property>
    
    <property name="clazz" ref="clazzOne">property>
    <property name="hobbies">
        <array>
            <value>抽烟value>
            <value>喝酒value>
            <value>烫头value>
        array>
    property>
    <property name="teacherMap" ref="teacherMap">property>
bean>

使用util:list、util:map标签必须引入相应的命名空间

<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">

9、实验八：p命名空间

引入p命名空间

<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"
       xmlns:p="http://www.springframework.org/schema/p"
       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">

引入p命名空间后，可以通过以下方式为bean的各个属性赋值

<bean id="studentSix" class="com.atguigu.spring6.bean.Student"
    p:id="1006" p:name="小明" p:clazz-ref="clazzOne" p:teacherMap-ref="teacherMap">bean>

10、实验九：引入外部属性文件

①加入依赖

 
<dependency>
    <groupId>mysqlgroupId>
    <artifactId>mysql-connector-javaartifactId>
    <version>8.0.30version>
dependency>


<dependency>
    <groupId>com.alibabagroupId>
    <artifactId>druidartifactId>
    <version>1.2.15version>
dependency>

②创建外部属性文件

jdbc.user=root
jdbc.password=gedeshidai
jdbc.url=jdbc:mysql://localhost:3306/ssm?serverTimezone=UTC
jdbc.driver=com.mysql.cj.jdbc.Driver

③引入属性文件

引入context 名称空间

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd">

beans>

<context:property-placeholder location="classpath:jdbc.properties"/>

注意：在使用 context:property-placeholder 元素加载外包配置文件功能前，首先需要在 XML 配置的一级标签 中添加 context 相关的约束。

④配置bean

<bean id="druidDataSource" class="com.alibaba.druid.pool.DruidDataSource">
    <property name="url" value="${jdbc.url}"/>
    <property name="driverClassName" value="${jdbc.driver}"/>
    <property name="username" value="${jdbc.user}"/>
    <property name="password" value="${jdbc.password}"/>
bean>

⑤测试

@Test
public void testDataSource() throws SQLException {
    ApplicationContext ac = new ClassPathXmlApplicationContext("spring-datasource.xml");
    DataSource dataSource = ac.getBean(DataSource.class);
    Connection connection = dataSource.getConnection();
    System.out.println(connection);
}

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总结

以上就是Spring之容器：IOC（2）的相关知识点，希望对你有所帮助。
积跬步以至千里，积怠惰以至深渊。时代在这跟着你一起努力哦！