Spring6梳理14——依赖注入之P命名空间

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

目录

①搭建模块

②引入配置文件

③创建bean-dip.xml文件

④创建课程类文件

⑤创建学生类文件

⑥创建老师类文件

⑦创建测试类文件

⑧运行截图

⑨总结

---

①搭建模块

搭建方式如：spring-first

②引入配置文件

引入spring-first模块配置文件：beans.xml、log4j2.xml

引入在父模块中

引入Pom.xml文件，具体内容如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.haozihua</groupId>
    <artifactId>spring6-ioc-xml</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>17</maven.compiler.source>
        <maven.compiler.target>17</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
    <dependencies>
        <!--spring context依赖-->
        <!--当你引入Spring Context依赖之后，表示将Spring的基础依赖引入了-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>6.0.2</version>
        </dependency>

        <!--junit5测试-->
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-api</artifactId>
            <version>5.6.3</version>
        </dependency>
        <!--log4j2的依赖-->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.19.0</version>
        </dependency>

        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-slf4j2-impl</artifactId>
            <version>2.19.0</version>
        </dependency>
    </dependencies>

</project>

引入log4j2文件，具体内容如下：

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <loggers>
        <!--
            level指定日志级别，从低到高的优先级：
                TRACE < DEBUG < INFO < WARN < ERROR < FATAL
                trace：追踪，是最低的日志级别，相当于追踪程序的执行
                debug：调试，一般在开发中，都将其设置为最低的日志级别
                info：信息，输出重要的信息，使用较多
                warn：警告，输出警告的信息
                error：错误，输出错误信息
                fatal：严重错误
        -->
        <root level="DEBUG">
            <appender-ref ref="spring6log"/>
            <appender-ref ref="RollingFile"/>
            <appender-ref ref="log"/>
        </root>
    </loggers>

    <appenders>
        <!--输出日志信息到控制台-->
        <console name="spring6log" target="SYSTEM_OUT">
            <!--控制日志输出的格式-->
            <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss SSS} [%t] %-3level %logger{1024} - %msg%n"/>
        </console>

        <!--文件会打印出所有信息，这个log每次运行程序会自动清空，由append属性决定，适合临时测试用-->
        <File name="log" fileName="H:/spring6_log/test.log" append="false">
            <PatternLayout pattern="%d{HH:mm:ss.SSS} %-5level %class{36} %L %M - %msg%xEx%n"/>
        </File>

        <!-- 这个会打印出所有的信息，
            每次大小超过size，
            则这size大小的日志会自动存入按年份-月份建立的文件夹下面并进行压缩，
            作为存档-->
        <RollingFile name="RollingFile" fileName="H:/spring6_log/app.log"
                     filePattern="log/$${date:yyyy-MM}/app-%d{MM-dd-yyyy}-%i.log.gz">
            <PatternLayout pattern="%d{yyyy-MM-dd 'at' HH:mm:ss z} %-5level %class{36} %L %M - %msg%xEx%n"/>
            <SizeBasedTriggeringPolicy size="50MB"/>
            <!-- DefaultRolloverStrategy属性如不设置，
            则默认为最多同一文件夹下7个文件，这里设置了20 -->
            <DefaultRolloverStrategy max="20"/>
        </RollingFile>
    </appenders>
</configuration>

③创建bean-dip.xml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"
       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">
    <!--
      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-->

    <!--p命名空间注入-->
    <bean id="studentp" class="com.atguigu.spring6.iocxml.diprename.Student"
    p:sid="100" p:sname="mary" p:lessonList-ref="lessonList" p:teacherMap-ref="teacherMap">
    </bean>

    <bean id="student" class="com.atguigu.spring6.iocxml.diprename.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.diprename.Lesson">
        <property name="lessonName" value="java开发"></property>
    </bean>
    <bean id="lessontwo" class="com.atguigu.spring6.iocxml.diprename.Lesson">
        <property name="lessonName" value="python开发"></property>
    </bean>

    <bean id="teacherone" class="com.atguigu.spring6.iocxml.diprename.Teacher">
        <property name="teacherId" value="101"></property>
        <property name="teacherName" value="贾宝玉"></property>
    </bean>
    <bean id="teachertwo" class="com.atguigu.spring6.iocxml.diprename.Teacher">
        <property name="teacherId" value="102"></property>
        <property name="teacherName" value="李时珍"></property>
    </bean>

</beans>

④创建课程类文件

package com.atguigu.spring6.iocxml.diprename;

/**
 * @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 + '\'' +
                '}';
    }
}

⑤创建学生类文件

package com.atguigu.spring6.iocxml.diprename;

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);
        }
    }
}

⑥创建老师类文件

package com.atguigu.spring6.iocxml.diprename;

/**
 * @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() {

        }

}

⑦创建测试类文件

package com.atguigu.spring6.iocxml.diprename;

import org.junit.jupiter.api.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
 * @package: com.atguigu.spring6.iocxml.dimap
 * @className: TestMap
 * @Description:
 * @author: haozihua
 * @date: 2024/8/20 15:50
 */
public class TestP {

    @Test
    public void Testp(){
        ApplicationContext context =
                new ClassPathXmlApplicationContext("bean-dip.xml");
        Student student = context.getBean("studentp", Student.class);
        student.run();
        System.out.println(student.getLessonList());
    }
}

⑧运行截图

⑨总结

与上一篇文章的运行结果类似，而P命名空间是通过p:实体类变量名="数值或者util集合"进行属性注入的，并通过测试类定义好的方法进行输出。总体来说较Property属性注入简便。