@Configuration
@ImportResource("classpath:/com/acme/properties-config.xml")
public class AppConfig {
  private @Value("${jdbc.url}") String url;
  private @Value("${jdbc.username}") String username;
  private @Value("${jdbc.password}") String password;

  public @Bean DataSource dataSource() {
      return new DriverManagerDataSource(url, username, password);
  }
}
/*---------------------------------*/
properties-config.xml
<beans>
  <context:property-placeholder location="classpath:/com/acme/jdbc.properties"/>
</beans>

/*---------------------------------*/
jdbc.properties
jdbc.url=jdbc:hsqldb:hsql://localhost/xdb
jdbc.username=sa
jdbc.password=