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The moose likes Programmer Certification (SCJP/OCPJP) and the fly likes poll() and peek() Big Moose Saloon
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JavaRanch » Java Forums » Certification » Programmer Certification (SCJP/OCPJP)
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poll() and peek()

chander shivdasani
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Joined: Oct 09, 2007
Posts: 206

I am having a hard time understanding the concept of poll() and peek() in priority queue. And also what is the natural order of sorting.


Enjoy, Chander
SCJP 5, Oracle Certified PL/SQL Developer
Nabila Mohammad
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Joined: Nov 05, 2007
Posts: 661
Poll removes the object from the Queue ,where as peek() simple retrives the object and does not remove it.
Natural ordering is ordering in a natural way.
For eg in String it would be Alphabetical order
In Numbers it would be Increasing order ...

Check out the api for further details.


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Chandra Bhatt
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Joined: Feb 28, 2007
Posts: 1707
Hi Chander,

May be this link makes some (if not much) sense for you:
http://www.coderanch.com/t/262787/java-programmer-SCJP/certification/PriorityQueue


cmbhatt
Chandra Bhatt
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Joined: Feb 28, 2007
Posts: 1707
Hi Chander,

Natural order of sorting:


1- Sorting numbers 323, 645, 43, 5, 53,2,654
Natural sorting (ascending order): 2,5,43,53,323,645,654
Natural sorting (descending order): 654, 645, 323, 53,43,5,2

2- Sorting characters: C, G, A, F, B, Z, X, T
A,B,C,F,G,X,T,Z

3- Sorting of String:
madan, chander, chandra, madam, carlos
carlos, chander, chandra, madam, madan


I think, if not going so verbose, the given examples make sense to understand the natural sorting order.
[ September 03, 2008: Message edited by: Chandra Bhatt ]
chander shivdasani
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Joined: Oct 09, 2007
Posts: 206

thanks a lot everyone.
 
 
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