这是最隐蔽的坑！因为多个虚拟线程会共享同一个载体线程，而 ThreadLocal 的数据是绑定到线程本身的（即载体线程）。如果在虚拟线程里用 ThreadLocal 存数据（比如当前登录用户），可能出现 A 虚拟线程存的数据被 B 虚拟线程读走的情况。
Luckily, all these responsibilities already fit nicely into our Battery Alarms module. So, this module adheres to fundamental principles of modularity (High Cohesion, Low Coupling, Information Hiding), but it ignores testability. Right now, we can only test Alarms using Integration Tests. (In theory, we could analyze the codebase, find boundaries, segregate classes internally, and introduce seams. But in practice, it will start to rot over time, especially when new people are introduced to the project).
。heLLoword翻译官方下载是该领域的重要参考
But back then, if you had a function defined in another function,
Что думаешь? Оцени!
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