title: Best practice for updating/writing to static variable?
body: <p>I have a project which displays department documentation. I store all the docs (get from database) in a static arrayList. Every X hour, I have that arrayList rebuilt based on the new doc (if any) from the database. There is also a static variable to control to rebuild that array or not, set and unset in a method which does the rebuild task. Each web browser hit the server will create this class's instance, but the doc arrayList and that control variable is shared among all the class instances. </p>
  
  <p>Find-Bugs tool complains that "Write to static field someArrayName and someVariableName from instance method someClassMethod". Seems this is not the good thing to do (let class instance method write to static field). Does anyone have good recommendation how to get around this problem ? Thanks.</p>