Introduction détaillée à Spring4

package com.mm.service;

public interface MessageService {
	String getMessage();
}

package com.mm.service.impl;

import com.mm.service.MessageService;

public class MessageServiceImpl implements MessageService{
	@Override
	public String getMessage() {
		return "hello mm";
	}
}

package com.mm.main.spring;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import com.mm.service.MessageService;
import com.mm.service.impl.MessageServiceImpl;

@Configuration
@ComponentScan(basePackages = "com.mm")
public class ApplicationConfig {
    @Bean
    MessageService messageService() {
        return new MessageServiceImpl();
    }
}

package com.mm.main.spring;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import com.mm.service.MessageService;

@Component
public class MessagePrinter {
	@Autowired
	private MessageService messageService;
	public void printMessage() {
        System.out.println(this.messageService.getMessage());
    }
}

package com.mm.main.spring;

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

public class Client {
	public static void main(String[] args) {
		ApplicationContext context=new AnnotationConfigApplicationContext(ApplicationConfig.class);
		MessagePrinter messagePrinter=context.getBean(MessagePrinter.class);
		messagePrinter.printMessage();
	}
}