Re: Some doubts about window start time and end time

[Jun Zhang]

Hi,Caizhi :
1.if I add offset , 
window(TumblingProcessingTimeWindows.of(Time.hours(6),Time.hours(-8)))
   it wil get a error: TumblingProcessingTimeWindows parameters must 
satisfy abs(offset) < size 
2.If it is caused by do not adding an offset, then why the same code, I set the 
window size to be an hour and there is no problem, and set the window size to 
six hours will be a problem?
                           
              
                    
 
     
 
     On 11/27/2019 18:21??Caizhi Weng<tsreape...@gmail.com&gt; wrote?? 
 
  Hi Jun,

You have to specify an offset when defining the windows. According to the Java 
docs of TumblingProcessingTimeWindows: "if you are living in somewhere which is 
not using UTC??00:00 time, such as China which is using UTC+08:00,and you want 
a time window with size of one day, and window begins at every 00:00:00 of 
local time,you may use {@code of(Time.days(1),Time.hours(-8))}. The parameter 
of offset is {@code Time.hours(-8))} since UTC+08:00 is 8 hours earlier than 
UTC time."


Does this solve the problem?
 

Jun Zhang <825875...@qq.com&gt; ??2019??11??27?????? ????6:03??????

           
                           
              
                           
              
Hi??Caizhi ??


the code like this :




dataStream
.keyBy(??device")
.window(TumblingProcessingTimeWindows.of(Time.hours(6)))
.trigger(ContinuousProcessingTimeTrigger.of(Time.seconds(5)))

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 &nbsp; .aggregate(new MyAggre(), new WindowResultFunction()) &nbsp; 
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;.print();



I add a trigger for quick output




On 11/27/2019 17:54??Caizhi Weng<tsreape...@gmail.com&gt; wrote?? 
 
  Hi Jun,

How do you define your window? Could you please show us the code?


Thanks.


Jun Zhang <825875...@qq.com&gt; ??2019??11??27?????? ????5:22??????

           
              ,              
Hi:
I defined a Tumbling window, I set the time size to one hour, and the resulting 
windows are [00: 00: 00-01: 00: 00], [01: 00: 00-02: 00: 00]. ....
This meets my expectations, but when I set the time size to 6 hours, the 
resulting window size is [02: 00: 00-08: 00: 00], [08: 00: 00-14: 00: 00], [14: 
00: 00-20: 00: 00] ...
But my expected window size is [00: 00: 00-06: 00: 00], [06: 00: 00-12: 00: 00] 
...
Is it right to get such a window result?



thanks