目录结构

pom.xml

<?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.geyao</groupId><artifactId>spring01geyao</artifactId><version>1.0-SNAPSHOT</version><dependencies><dependency><groupId>org.springframework</groupId><artifactId>spring-context</artifactId><version>4.3.13.RELEASE</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-test</artifactId><version>3.2.0.RELEASE</version></dependency><dependency><groupId>log4j</groupId><artifactId>log4j</artifactId><version>1.2.17</version></dependency><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.12</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-test</artifactId><version>4.3.4.RELEASE</version><scope>test</scope></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-test</artifactId><version>4.3.4.RELEASE</version><scope>test</scope></dependency></dependencies>
</project>

log4j.properties

### 设置###
log4j.rootLogger = ERROR,stdout### 输出信息到控制抬 ###
log4j.appender.stdout = org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout = org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern = [%-5p] %d{yyyy-MM-dd HH:mm:ss,SSS} method:%l%n%m%n
log4j.category.org.springframework.beans.factory=ERROR

applicationContext.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"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"><!--bean元素：描述当前的对象需要由spring容器管理id属性：标识对象 未来在应用程序中可以根据id获取对象class对象：被管理的对象的全名--><bean id="notepad" class="com.geyao.demo.NotePad"/>
</beans>

notepad类

package com.geyao.demo;public class NotePad {public NotePad() {super();System.out.println("NotePad的构造函数"+this.toString());}
}

Notepadtest类

package com.geyao.demo;import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;
//无论我们是否去主动获取对象，spring上下文刚加载就会创建对象
//无论获取多少次，都是统一对象
//
public class NotepadTest {@Testpublic void test01(){ClassPathXmlApplicationContext context=new ClassPathXmlApplicationContext("applicationContext.xml");NotePad notePad1= (NotePad)context.getBean("notepad");NotePad notePad2= (NotePad)context.getBean("notepad");System.out.println(notePad1=notePad2);}
}

notepadtestAuto类

package com.geyao.demo;import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class NotePadTestAuto {@Autowiredprivate NotePad notePad1;@Autowiredprivate NotePad notePad2;@Testpublic void test01(){System.out.println(notePad1==notePad2);}
}

运行结果

NotePad的构造函数com.geyao.demo.NotePad@20ccf40b
true