Spring学习（6）—— IOC容器-Bean管理（注解方式）完全注解开发

本文介绍了如何在Spring Boot项目中使用Java配置类替换XML配置，包括@Configuration注解和@ComponentScan的使用。通过实例演示了如何加载配置类并获取Bean。

一. 创建配置类来代替xml配置文件

添加@Configuration让类成为配置类；

添加@ComponentScan(basePackages = {" "})，在basePackages添加要扫描的包

package config;

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

@Configuration
@ComponentScan(basePackages = {"pojo","service","dao"})
public class SpringConfig {

}

二. 加载配置类

将原本加载配置文件换成加载配置类

package pojo;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

@Component
public class User {
    @Value(value = "Tom")
    private String userName;

    @Value(value = "123456")
    private String password;

    @Override
    public String toString() {
        return "User{" +
                "userName='" + userName + '\'' +
                ", password='" + password + '\'' +
                '}';
    }
}

import config.SpringConfig;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import pojo.User;

public class testSpring {
    @Test
    public void test() {
        //加载配置类
        ApplicationContext context = new AnnotationConfigApplicationContext(SpringConfig.class);

        User user = context.getBean("user", User.class);

        System.out.println(user.toString());  //User{userName='Tom', password='123456'}
    }
}