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Posted to user@spark.apache.org by chen yong <cy...@hotmail.com> on 2016/10/01 13:35:08 UTC
execution sequence puzzle
Hello everybody,
I am puzzled by the execution sequence of the following scala program. Please tell me if it run in the same sequence on your computer,.and it is normal.
Thanks
execution sequence according to line number: 26-7-20-27-9-10-12-13-15-7-20-17-18-9-10-12-13-15-7-20-17-18
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import scala.collection.mutable.ArrayBuffer
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object TestCase1{
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def func(testtttt:Iterator[(Int,Long)]): Iterator[(Int,Long)]={
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println("in")
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val testtttt1=testtttt.flatmap{
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case(item,count)=>
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val newPrefix=item
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println(count)
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val a=Iterator.single((newPrefix,count))
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func(a)
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val c = a
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c
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}
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testtttt1
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}
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def main(args: Array[String]){
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val freqItems = ArrayBuffer((2,3L),(3,2L),(4,1L))
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val testtttt = freqItems.toIterator
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val result = func(testtttt)
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val reer = result.toArray
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}
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}