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What does "polls data from web services" mean? Could you give me some examples? Also, what are the requirements for this kind of application?

Michael Petrotta
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kanna
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  • It's not 'polling' and it should be 'pulling', also this is not the correct place to ask this kind of question here – Simon Wang Oct 20 '12 at 01:58

1 Answers1

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In pseudocode:

while (!done) {
   answer = webService.service()
   if (!done = processAnswer(answer)) // display data, etc.
      wait(interval); //wait for some time period
}

So basically, you are calling a web service repeatedly, waiting some time interval in between. You might be watching to see if some long operation is finished, or be looking for new data when the web service is called. An example might be an email client that calls the server to see if new mail arrived since the last call. Polling is used when you don't have a mechanism to be notified (push notification).

jalynn2
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