springBoot项目中使用@Value取值出现的问题及解决

@Value("${file.uploadFolder}")
    private String uploadFolder;

private static String uploadFolder;
public static String getUploadFolder() {
        return uploadFolder;
    }
    @Value("${file.uploadFolder}")
    public  void setUploadFolder(String uploadFolder) {
        Base64Utils.uploadFolder = uploadFolder;
    }

server.port=8007
#Mysql配置
url=jdbc:mysql://localhost:3306/lzy_zyg?useUnicode=true&characterEncoding=UTF-8
username=root
passWord=root

@Configuration
public class JfinalDb
{
    @Value("${url}")
    private String dbUrl;
    @Value("${username}")
    private String dbUName;
    @Value("${password}")
    private String dbPwd;
...
}