@Component
@ConditionalOnProperty(prefix = "jwt", name = "enable",havingValue = "true")
public class JwtUtil {

   private static String header = "";
   private static String username = "";
   private static String password = "";

   @Autowired
   private Environment env;

   public JwtUtil(Environment env) {
      this.env = env;
   }

   @PostConstruct
   public void config() {
      url = env.getProperty("spring.datasource.url");
      username = env.getProperty("spring.datasource.username");
      password = env.getProperty("spring.datasource.password");
   }

注意加开关