Re: clear method on Window Trigger

2018-07-17 Thread Hequn Cheng
Hi Soheil, The clear() method performs any action needed upon removal of the corresponding window. This is called when a window is purged. The differences between FIRE and FIRE_AND_PURGE is FIRE only trigger the computation while FIRE_AND_PURGE trigger the computation and clear the elements in

Re: clear method on Window Trigger

2018-07-17 Thread vino yang
Hi Soheil, Did you read the documentation about Flink Window/Trigger [1]? FIRE_AND_PURGE usually used to implement the count window. Flink provide a PurgingTrigger as a warper for other trigger to make those triggers can be purge. One of this class use case is count window[2][3]. About your

clear method on Window Trigger

2018-07-17 Thread Soheil Pourbafrani
Hi, Can someone elaborate on when the clear method on class Trigger will be called and what is the duty of that? Also, I don't know what is the benefit of FIRE_AND_PURGE against FIRE and it's use case. For example, in a scenario, if we have a count of 3 Window that also will trigger after a