Another scenario would be a dirtyread where the value is in the process of being updated and another thread reads an old value.
另外一种情况是误读（dirty read），即一个数值正在被修改而另外一个进程读了一个修改前的值。
2
I read it every day and feel dirty all over.
我每天都看，感觉世界一片肮脏。
3
Access flags for read-only getter methods, to ensure that Entity EJB instances aren't marked as dirty and persisted into the database unnecessarily when they are read but not updated.