SpringBoot入门(二) springBoot使用yml配置

秒速五厘米 2022-05-29 04:16 237阅读 0赞

1.yml的标准结构

version: 2.0
    server:
     port: 8081
     
    spring:
     application:
      name: ztest-spb
     profiles:
      active: dev

2.系统中调用 格式

env.getProperty("version"),
            env.getProperty("spring.application.name"),
            env.getProperty("spring.profiles.active"),
            env.getProperty("server.port")

3.注意 :号后边和值要有空格 如   version: 2.0  禁止 version:2.0

Caused by: org.yaml.snakeyaml.scanner.ScannerException: while scanning for the next token  
found character '\\t(TAB)' that cannot start any token. (Do not use \\t(TAB) for indentation)

in 'reader', line 3, column 2:

.yml文本中禁止使用tab 做间隔 否则报以上错误

4.yml的赋值使用

(1)使用特定的 @value\*yml注解 给类中的属性注值 (类似从属性文件获取数据然后赋值)

@RestController
    public class TestController {
    	
    	@Value(value="${spring.application.name}")
    	private  String projectname;
    	
    	@RequestMapping("/hello")
    	public  String hello(){
    		return "hello "+projectname;
    	}
    }

![Image 1][]

(2)将属性文件中的值 直接赋值给定义的对象

user

username: 111

age: king       //将属性赋值给对象

import org.springframework.boot.context.properties.ConfigurationProperties;
    import org.springframework.stereotype.Component;
    
    @Component
    @ConfigurationProperties(prefix = "user")
    public class UserProperties {
    
        private String username;
    
        private Integer age;
    
        public String getUsername() {
            return username;
        }
    
        public void setUsername(String username) {
            this.username= username;
        }
    
        public Integer getAge() {
            return age;
        }
    
        public void setAge(Integer age) {
            this.age = age;
        }
    }

在类中直接自动装配就可以使用了

@RestController
    public class Test2Controller {
    	
    	@Autowired
    	UserProperties properties;
    	
    	@RequestMapping("/hello")
    	public  String hello(){
    		return "hello "+properties.getUsername();
    	}
    }

[Image 1]: