Spring基于java注解方式注册javabean关键代码：AnnotationConfigApplicationContext

    4.0.0

    com.burns.spring.framework.test
    spring-framework-test-20220516
    1.0-SNAPSHOT

    
        8
        8
    

    
        
            
                org.springframework.boot
                spring-boot-starter-parent
                2.5.13
                import
                pom
            
        
    

    
        
            org.springframework
            spring-context
        
    

package com.burns.spring.framework.test;

import com.burns.spring.framework.test.component.MessagePrinter;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Scope;

@ComponentScan
public class Application {
    public static void main(String[] args) {
        ApplicationContext context = new AnnotationConfigApplicationContext(Application.class);
        MessagePrinter printer = context.getBean(MessagePrinter.class);
        printer.pringMessage();
    }
}

package com.burns.spring.framework.test.component;

import com.burns.spring.framework.test.service.MessageService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

@Component
public class MessagePrinter {
    final private MessageService messageService;

    @Autowired
    public MessagePrinter(MessageService messageService) {
        this.messageService = messageService;
    }

    public void pringMessage() {
        System.out.println(this.messageService.getMessage());
    }


}

package com.burns.spring.framework.test.service;

public interface MessageService {
    String getMessage();

}

package com.burns.spring.framework.test.service.impl;

import com.burns.spring.framework.test.service.MessageService;
import org.springframework.stereotype.Service;

@Service
public class MessageServiceImpl implements MessageService {
    @Override
    public String getMessage() {
        return "Hello World!";
    }
}