这样，当再次同步目录时，就可以像一般情况一样比较源和目标文件并判断出差异。

This is needed so that when the directories are synchronized again, the source and destination files can be compared and the list of differences determined as usual.

youdao

而这种偏爱与大脑中的价值判断被同步激活。

That preference went hand in hand with the activation of a part of the brain involved in value judgment.

youdao

使用ThreadLocal使我们可以绕过为实现线程安全而对何时需要同步进行判断的复杂过程，而且因为它不需要任何同步，所以也改善了可伸缩性。

Using ThreadLocal allows us to bypass the complexity of determining when to synchronize in order to achieve thread-safety, and it improves scalability because it doesn't require any synchronization.

youdao