SpringBoot入门

新建工程:Spring Initializr
SpringBoot就会帮我们建好SpringbootApplication启动类
内容:

package com.fitsoft.springboot;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringbootApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringbootApplication.class, args);
    }

}

这里举一个简单的例子来使用:
在resources资源目录下新建application.yml配置文件(比application.properties好用,易维护)
内容:

spring:
  profiles:
    active: prd

其中prd代表生产环境
application-prd.yml内容:

server:
  port: 80
debug: false
logging:
  level:
    root: info
  file: E:/demospringboot.log
spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/test
    data-username: root
    data-password: root
mall:
  config:
    name: 优美商城
    description: 这是一家化妆品特卖网站
    hot-sales: 20
    show-advert: true

dev代表测试环境
application-dev.yml内容:

debug: true
logging:
  level:
    root: info
  file: E:/demospringboot.log
spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/test
    data-username: root
    data-password: root
mall:
  config:
    name: 爱美商城
    description: 这是一家化妆品特卖网站
    hot-sales: 20
    show-advert: true

这里我们使用的是生产环境举例,端口号为80
新建MyController类

package com.fitsoft.springboot.controller;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

/**
 * @author Joker
 * @since 2019/9/14 0014 22:36
 */
@Controller
public class MyController {

    @Value("${mall.config.name}")
    private String name;

    @Value("${mall.config.description}")
    private String description;

    @Value("${mall.config.hot-sales}")
    private Integer hotSales;

    @Value("${mall.config.show-advert}")
    private Boolean showAdvert;

//    @RequestMapping("/out")
//    @ResponseBody
//    public String out(){
//        return "success";
//    }

    @RequestMapping("/info")
    @ResponseBody
    public String info(){
        return String.format("name:%s,description:%s,hot-sales:%s,show-advert:%s",
                name, description, hotSales, showAdvert);
    }
}

这里使用@Value注解来访问yml文件,并读取配置,运行一下:
效果图:

![](https://i.loli.net/2019/09/15/oJsxgzR8CybXufP.png)

真香...

原文地址:https://www.cnblogs.com/zqm-sau/p/11521558.html