1、自定义了配置文件

praise.siteName = mahalalel
praise.siteUrl = http://127.0.0.1

2、配置文件配置

@ConfigurationProperties(prefix = "praise", value = "site.properties")

3、启动应用

报如下错误

In AnnotationAttributes for annotation [org.springframework.boot.context.properties.ConfigurationProperties] declared on class 'com.xxx.config.SiteConfig', 
attribute 'prefix' and its alias 'value' are declared with values of [praise] and [site.properties], 
but only one is permitted.

错误原因在于，注解ConfigurationProperties的属性prefix和value不能同时使用

4、修改并验证

@ConfigurationProperties(prefix = "praise")
public class SiteConfig {

    private String siteName;

    private String siteUrl;
    // get/set方法省略
}

控制器内调用

@RestController
@RequestMapping("/task")
public class TaskController {

    @Autowired
    private SiteConfig siteConfig;

    @GetMapping("/hello")
    public String hello(){
        String siteName = siteConfig.getSiteName();
        return "Hello Task!!!!" + siteName;
    }
}

访问地址：http://localhost:8081/task/hello
页面显示：

Hello Task!!!!mahalalel