初识springboot笔记
2018-01-08 本文已影响0人
Amber_cd43
一、配置文件
方法1:application.properties中的写法
![](https://img.haomeiwen.com/i9532102/16b900bfb5d0f6a5.png)
方法2:application.yml中写法
![](https://img.haomeiwen.com/i9532102/71f6add1cba04e23.png)
二、注解的使用
1、@Value()
@Value()注解,实现配置内容的注入, 把Application.yml文件中设置的值取出来。
@Value(${type}),例如此处取的是type的值 当配置内容较多时,建议对配置内容进行分组。
在.yml中写法,属性顶格写:
![](https://img.haomeiwen.com/i9532102/bdc46d073a774126.png)
![](https://img.haomeiwen.com/i9532102/d3b46aae2433c404.png)
![](https://img.haomeiwen.com/i9532102/d1ec3f0c38739743.png)
2、@Component、@ConfigurationProperties
对配置内容进行分组,不是每个值都写@Value注解
在Application.yml文件中,设置girl,下面有两个属性type和age
![](https://img.haomeiwen.com/i9532102/2a5c3146266e5a7b.png)
![](https://img.haomeiwen.com/i9532102/e55869253c2a36bd.png)
![](https://img.haomeiwen.com/i9532102/4755391a56562214.png)
![](https://img.haomeiwen.com/i9532102/7a5f7ce63debffb6.png)
3、Controller的使用
![](https://img.haomeiwen.com/i9532102/38d2c76f16213053.png)
3.1、@RestController
@RestController等同于@ResponseBody和@Controller的组合。
3.2、@RequestMapping
访问多个路径到同一个位置,使用@RequestMapping,将url写成集合格式
![](https://img.haomeiwen.com/i9532102/399ff9d5a72fe7ea.png)
给整个类,指定一个url
![](https://img.haomeiwen.com/i9532102/22cc2896e326b4e7.png)
![](https://img.haomeiwen.com/i9532102/9a452f9299e3ae1a.png)
3.3 @PathVariable获取url中数据
![](https://img.haomeiwen.com/i9532102/0f48dc5343944fbb.png)
![](https://img.haomeiwen.com/i9532102/1da942d2b17199bf.png)
3.4@RequestParam获取url中的数据值:
![](https://img.haomeiwen.com/i9532102/514ab63e20096804.png)
![](https://img.haomeiwen.com/i9532102/77af0e0e8392c686.png)
当传入参数为空时,设置默认值
![](https://img.haomeiwen.com/i9532102/c04f864a2929fa03.png)
![](https://img.haomeiwen.com/i9532102/2657f72c7bde4c3b.png)