Java实现多个线程（excel处理）

So my application allows the user to select Microsoft excel file(s), usually having between 300 to 5000 rows. At times even larger than 5000. My question is would it be more efficient to use multiple threads in this scenario and what is the most effective way to then utilize the threads. Should each file have a thread of its own or what ? Also this is how each excel file is processed:So my application allows the user to select Mic