Win a copy of Escape Velocity: Better Metrics for Agile Teams this week in the Agile and Other Processes forum!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other Pie Elite all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Liutauras Vilda
  • Tim Cooke
  • Paul Clapham
  • Jeanne Boyarsky
Sheriffs:
  • Ron McLeod
  • Frank Carver
  • Junilu Lacar
Saloon Keepers:
  • Stephan van Hulst
  • Tim Moores
  • Tim Holloway
  • Al Hobbs
  • Carey Brown
Bartenders:
  • Piet Souris
  • Frits Walraven
  • fred rosenberger

doubt for PriorityQueue

 
Ranch Hand
Posts: 383
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I have doubt for PriorityQueue from K & B(java 5) book at page no:567.
output is:

peek 9-how it is 9?
As they have mentioned highest priority is 1 on page 566.
So the answer would be 1 for both peek & poll methods.

poll 9-same here.

Can anybody clear my doubt?
Thanks in advance.
 
Ranch Hand
Posts: 377
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Originally posted by dolly shah:
As they have mentioned highest priority is 1 on page 566.



If you read the text on page 566 a second time, you will notice that this is only an example. You can use any ordering for the queue.

And this is demonstrated in the example.
 
dolly shah
Ranch Hand
Posts: 383
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
But on page 567:they have explained about this example and have written that peek gives highest priority which is 9, but when I run this example it gives me 1 instead of 9. So what about that/
 
Ranch Hand
Posts: 32
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I ran it and got 9.
 
dolly shah
Ranch Hand
Posts: 383
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Thanks. Even I got 9 now. But still I have question, the elements are returned in priority order, So why 9 is highest priority instead of 1. Also what is "10" in comparator it is supposed to be "ia".
 
Manfred Klug
Ranch Hand
Posts: 377
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Originally posted by dolly shah:
the elements are returned in priority order, So why 9 is highest priority instead of 1.


The sorting of the queue specifies the priority. The answer for your question is the comparator of pq2.

Also what is "10" in comparator it is supposed to be "ia".


Have a look at the API documentation for PriorityQueue.
 
dolly shah
Ranch Hand
Posts: 383
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Thanks for this details.
For second question the answer is below. Am I right?

PriorityQueue()
Creates a PriorityQueue with the default initial capacity (11) that orders its elements according to their natural ordering (using Comparable).
 
if you think brussel sprouts are yummy, you should try any other food. And this tiny ad:
Garden Master Course kickstarter
https://coderanch.com/t/754577/Garden-Master-kickstarter
reply
    Bookmark Topic Watch Topic
  • New Topic