This skips out the intermediary step of obtaining a ServiceReference, but does require that you call open after construction, in order to begin tracking services.

这就跳过了中间获得ServiceReference的几步，但是要求你在构造之后调用open，以便开始跟踪服务。

youdao

There are some subtle complexities in looking up a service which are exposed when not using a service, such as when a ServiceReference becomes unavailable but before it is resolved into a service.

在没有使用服务的情况下，查找已输出的服务稍微有点复杂：比如，ServiceReference在其被解析为一个服务之前突然变得不可用了。

youdao