如果spring boot无法使用JNDI查找创建数据源，如何创建回退

@Configuration
public class DataSourceConfig {

    @Value("${spring.datasource.url}")
    private String url;

    @Value("${spring.datasource.username}")
    private String username;

    @Value("${spring.datasource.password}")
    private String password;

    @Bean
    public DataSource dataSource() {
        // 创建HikariCP数据源
        HikariDataSource dataSource = new HikariDataSource();
        dataSource.setJdbcUrl(url);
        dataSource.setUsername(username);
        dataSource.setPassword(password);
        return dataSource;
    }
}

@Repository
public class UserRepository {

    @Autowired
    private DataSource dataSource;

    public User getUserById(int id) {
        // 使用数据源进行数据库查询操作
        // ...
    }
}