<!--lombok依賴-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>

package com.example.bean;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.ToString;

@Data                   //setter和getter方法
@ToString               //toString方法
@AllArgsConstructor     //有參構造器
@NoArgsConstructor      //無參構造器
@EqualsAndHashCode		//EqualsAndHashCode方法
public class User {
    private Integer id;
    private String username;
    private String password;
}

package com.example.controller;

import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

//@RestController可以理解成是Controller加ResponseBody
@RestController
@Slf4j
public class HelloController {

    @RequestMapping("/hello")
    public String toHello(@RequestParam("name") String name){
        log.info("/hello被人訪問啦！");
        return "Hello,World!"+name;
    }
}

package com.example.boot;

import com.example.bean.User;
import com.example.config.MyConfig;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;

/**
 * 主程序類
 * @SpringBootApplication 告訴 SpringBoot這是一個SpringBoot應用
 */
@SpringBootApplication(scanBasePackages = "com.example")
public class MainApplication {
    public static void main(String[] args) {
        //固定寫法
        ConfigurableApplicationContext run = SpringApplication.run(MainApplication.class, args);
        
        MyConfig myConfig = run.getBean(MyConfig.class);
        //通過myConfig的方法獲取Bean
        User user = myConfig.user();
//        User user1 = myConfig.user();
        //通過run獲取Bean
        User user2 = run.getBean("user",User.class);
        System.out.println(user);
        System.out.println(user2);
    }
}

        <!--dev-tools依賴-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>