spring 中 @import的用法

第一步： 新建Java工程    FirstSpringJAVA

第二步：导入相关的spring jar包

 <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>4.3.1.RELEASE</version>
    </dependency>
    
     <dependency>  
            <groupId>org.springframework</groupId>  
            <artifactId>spring-beans</artifactId>  
            <version>4.3.1.RELEASE</version>  
            <type>jar</type>  
        </dependency>  
  
        <dependency>  
            <groupId>org.springframework</groupId>  
            <artifactId>spring-webmvc</artifactId>  
            <version>4.3.1.RELEASE</version>  
            <type>jar</type>  
        </dependency>  
  
        <dependency>  
            <groupId>org.springframework</groupId>  
            <artifactId>spring-orm</artifactId>  
            <version>4.3.1.RELEASE</version>  
            <type>jar</type>  
        </dependency>  

第三步： 新建接口

Father.java

package com.xuzhiwen.spring5;

public interface Father {
    public abstract void sing();
}

第四步：新建两个接口实现类

Son1.java

package com.xuzhiwen.spring5;

public class Son1 implements Father{
    @Override
    public void sing() {
        System.out.println("son1 sing()...");
    }
}

Son2.java

package com.xuzhiwen.spring5;

public class Son2 implements Father{
    @Override
    public void sing() {
        System.out.println("son2 sing()...");
    }
}

第五步：编写针对上面两个类的配置文件

Son1Config.java

package com.xuzhiwen.spring5;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class Son1Config {
    
    @Bean(name="son1")
    public Father getFather(){
        return new Son1();
    }
}

Son2Config.java

package com.xuzhiwen.spring5;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class Son2Config {
    
    @Bean(name="son2")
    public Father getFather(){
        return new Son2();
    }
}

第六步： 将两个配置文件的内容合并到一起

AppConfigTogether.java

package com.xuzhiwen.spring5;

import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;

@Configuration
@Import({Son1Config.class,Son2Config.class})
public class AppConfigTogether {
    
}

第七步：编写测试类

Test.java

package com.xuzhiwen.spring5;

import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class Test {
    public static void main(String[] args) {
        ApplicationContext app = new AnnotationConfigApplicationContext(AppConfigTogether.class);
        Father father1 = (Father) app.getBean("son1");
        Father father2 = (Father) app.getBean("son2");
        father1.sing();
        father2.sing();
    }
}

第八步：运行结果如下

第九步： Java文件目录结构如下