@Controller

@SpringBootApplication

@Configuration

@ComponentScan(basePackages={"first","third"})   //配置扫描包

@PropertySource(value={"classpath:jdbc.properties"})  //指定读取配置文件

public class HelloApplication {

    @Value("${url}")

    private String url;

    @Bean

    public DataSource dataSource() {

        System.out.println(url);

        DruidDataSource ds = new DruidDataSource();

        ds.setUrl(url);

        return ds;

    }

    public static void main(String[] args) {

        SpringApplication.run(HelloApplication.class, args);

    }

}