Hello Spring

 

 

 

开发一个Spring项目

工具:idea

新建一个maven项目

添加相关的maven依赖

 <!-- https://mvnrepository.com/artifact/org.springframework/spring-beans -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>4.2.0.RELEASE</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.2.0.RELEASE</version>
        </dependency>

       spring-beans.4.2.0.jar
   附带了core核心 和commons-logging

       spring-context.4.2.0.jar

         spring-expression.4.2.0.jar

         spring-aoplple.4.2.0.jar

         spring-aop.4.2.0.jar

这两个依赖会下载和它相关的jar

引入日志

<!--日志的jar-->
<dependency>
    <groupId>log4j</groupId>
    <artifactId>log4j</artifactId>
    <version>1.2.17</version>
</dependency>
添加log4j.properties文件

log4j.rootLogger=info,con
#日志的输出级别是info,输出源是con
#定义输出源的输出位置是控制台
log4j.appender.con=org.apache.log4j.ConsoleAppender
#定义输出日志的布局采用的类
log4j.appender.con.layout=org.apache.log4j.PatternLayout
#定义日志输出的布局
log4j.appender.con.layout.ConversionPattern=%d{MM-dd HH:mm:ss}[%p]%c%n -%m%n

日志输出图:

编写HelloSpring类

package cn.baby.entity;

/**
 * Created by Administrator on 2017/10/18.
 */
public class HelloSpring {
    private String who=null;

    public String getWho() {
        return who;
    }

    public void setWho(String who) {
        this.who = who;
    }

    //输出方法
    public void print(){
        System.out.println("Hello,"+this.getWho()+"!");
    }
}

编写Spring配置文件

applicationContext-hello.xml

<?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:p="http://www.springframework.org/schema/p"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
">
    <!--通过bean元素声明需要Spring创建的实例.该实例属性的类型通过class属性来指定并通过id属性为实例指定一个名称,以便于访问-->
    <bean id="helloSpring" class="cn.baby.entity.HelloSpring">
        <!--通过property元素用来为实例的属性赋值-->
        <property name="who">
            <value>Spring</value>
        </property>
    </bean>

</beans>

编写测试方法

 @Test
    public void show()
    {
        //实例化Spring
        ApplicationContext context=new ClassPathXmlApplicationContext("applicationContext-hello.xml");
        //通过ApplicationContext的getBen方法,根据id来获取Bean的实例
        HelloSpring hellospring = (HelloSpring) context.getBean("helloSpring");
        hellospring.print();
    }