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Comparator question

Graham VMead
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Joined: Sep 22, 2003
Posts: 154
Hi,

I want to sort a list of session beans by their string session keys so I implemented the following.



If I want to search this sorted list using Collections.binarySearch with the search key as a String and using the same comparator how do I know whether objA or objB will be the search String and which will be the bean.

Will I need to do the following



Hope this makes sense, I know I should be checking the bean class and throwing ClassCastExceptions etc but I've left it out for clarity.
[ July 07, 2006: Message edited by: Graham VMead ]
Ernest Friedman-Hill
author and iconoclast
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Joined: Jul 08, 2003
Posts: 24183
    
  34

There's no other obvious way to do it; what you've done makes perfect sense.

Regarding type-checking: it's generally considered OK to just cast obliviously in Comparators, without explicit checking. When you call sort() using such a Comparator, then it would make sense to catch ClassCastException.


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Graham VMead
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Joined: Sep 22, 2003
Posts: 154
Thanks for the reply Ernest: Thats what I'll do then
 
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subject: Comparator question