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many comparator classes?

H Melua
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Joined: Jan 04, 2005
Posts: 172
hello

i wrote a program that has alot of sorting methods, is there a way of going it without having too many comparator classes??

thank u
hannah
[ January 23, 2005: Message edited by: H Melua ]
M Beck
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Joined: Jan 14, 2005
Posts: 323
i don't know - why would you use more than one or two per datatype?

most sorting algorithms use a comparison operation to determine which of two things should be sorted before the other. usually, if you're writing your own comparison code, it's either because (1) you want to sort things in some unusual and tricky order, such that the simple built-in "<" / ">" operators won't do the job; or (2) because the things you want to compare are complex, derived data types that those built-in operators just don't work on.

it seems to me that, either way, you would usually need no more than two comparators for each type of thing; one to compare "is less than" and the other for "is greater than". then you should be able to decide whether to sort in ascending or descending order by simply passing one or the other of those to your sorting algorithm. am i right, or am i confused?

two comparators per datatype doesn't seem like a whole lot to me, i guess is what i'm saying. how many have you got?
Jeroen Wenting
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Joined: Oct 12, 2000
Posts: 5093
I usually implement Comparable rather than providing a Comparator, but I must admit most of the sorting I need to do is rather simplistic


42
H Melua
Ranch Hand

Joined: Jan 04, 2005
Posts: 172
hiii

well true, but i just wanted to know for the sake of efficiency thats all.
I have implemented comparable and also comparators, since i need 4 sorting orders, and i do think 3 is alot :roll: for comparator!!! and even if it wasnt that much, im still wondering if there is a better way...

thanks for replying
hannah
[ January 23, 2005: Message edited by: H Melua ]
 
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