package com.spring.test.helloWorld;

public interface HelloWorld {
    
    public void sayHello();
     
}

package com.spring.test.helloWorld;

public class HelloWorldService {
      
    private HelloWorld helloWorld;
  
    public HelloWorldService() {
  
    }
  
    public void setHelloWorld(HelloWorld helloWorld) {
        this.helloWorld = helloWorld;
    }
  
    public HelloWorld getHelloWorld() {
        return this.helloWorld;
    }
  
}

package com.spring.test.helloWorld.impl;

import com.spring.test.helloWorld.HelloWorld;

public class SpringHelloWorld implements HelloWorld {
      
    @Override
    public void sayHello() {
        System.out.println("Spring Say Hello!!");
    }
  
}

package com.spring.test.helloWorld.impl;

import com.spring.test.helloWorld.HelloWorld;

public class StrutsHelloWorld implements HelloWorld {
      
    @Override
    public void sayHello() {
        System.out.println("Struts Say Hello!!");
    }
  
}

<?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 id="springHelloWorld"
        class="com.spring.test.helloWorld.impl.SpringHelloWorld"></bean>
    <bean id="strutsHelloWorld"
        class="com.spring.test.helloWorld.impl.StrutsHelloWorld"></bean>
  
    <bean id="helloWorldService"
        class="com.spring.test.helloWorld.HelloWorldService">
        <property name="helloWorld" ref="springHelloWorld"/>
    </bean>
  
</beans>

<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.spring</groupId>
  <artifactId>Spring</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <dependencies>
 
        <!-- Spring Core -->
        <!-- http://mvnrepository.com/artifact/org.springframework/spring-core -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>4.1.4.RELEASE</version>
        </dependency>
         
        <!-- Spring Context -->
        <!-- http://mvnrepository.com/artifact/org.springframework/spring-context -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.1.4.RELEASE</version>
        </dependency>
  </dependencies>
</project>

package com.spring.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.spring.test.helloWorld.HelloWorld;
import com.spring.test.helloWorld.HelloWorldService;
public class HelloProgram {
    public static void main(String[] args) {
        
        ApplicationContext context =
                new ClassPathXmlApplicationContext("beans.xml");//读取beans.xml 文件来创建一个应用程序上下文对象
         
        HelloWorldService service =
             (HelloWorldService) context.getBean("helloWorldService");
          
        HelloWorld hw= service.getHelloWorld();
         
        hw.sayHello();
    }
}

<?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 id="springHelloWorld"
        class="com.spring.test.helloWorld.impl.SpringHelloWorld"></bean>
    <bean id="strutsHelloWorld"
        class="com.spring.test.helloWorld.impl.StrutsHelloWorld"></bean>
  
    <bean id="helloWorldService"
        class="com.spring.test.helloWorld.HelloWorldService">
        <property name="helloWorld" ref="strutsHelloWorld"/><!-- IoC容器创建strutsHelloWorld对象并通过setter方法注入依赖 -->
    </bean>
  
</beans>