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Natural order in collections

vendikonda sravan
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Joined: May 09, 2010
Posts: 38
Can Some one help me understanding natural order in collections ?
what dose it mean when we say a collection is sorted in natural order?

Thanks
Rob Spoor
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Joined: Oct 27, 2005
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  18

It depends on the objects. For Integer it means that, for instance, 1 < 2 and 4 < 5. For strings its lexicographical comparison: Rob > Prime because "R" comes after "P". For other classes it's defined by how the compareTo method (as required by implementing Comparable) is implemented.


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Jim Hoglund
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Joined: Jan 09, 2008
Posts: 525
Natural order is counting order, or alphabetical order, or date order,
or smallest to largest order, or is it largest to smallest order? Either
way is okay. This term is generally used somewhat informally so if there
is any question, make sure to find out what it means in a particular context.

Jim ... ...


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Jim Hoglund
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Joined: Jan 09, 2008
Posts: 525
Ey Rob : Digging slightly deeper into lexical land, natural order is:
(smallest) white space => digits => upper case => lower case (largest).
Punctuation and special characters are spread between these groups.

Jim ... ...
Rob Spoor
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Joined: Oct 27, 2005
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  18

If you want to be precise, in Java it's based on the int value of the individual chars, with the first 127 available on http://www.asciitable.com.
Jim Hoglund
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Joined: Jan 09, 2008
Posts: 525
So a 32-bit (signed) integer conveniently covers the 16-bit UniCode space
of primitive type char. It's interesting that 0x00 is sometimes called "null"
in ASCII land, which of course it is not - it's zero.

Jim ... ...
vendikonda sravan
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Joined: May 09, 2010
Posts: 38
Thanks Guys
Rob Spoor
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Joined: Oct 27, 2005
Posts: 19649
    
  18

Jim Hoglund wrote:It's interesting that 0x00 is sometimes called "null"
in ASCII land, which of course it is not - it's zero.

I'd still call it NULL. Not only is that how it's defined in C (you know, the NULL character to terminate strings), but if you call it "zero" people may mistake it for '0' -- or 0x30.
 
Don't get me started about those stupid light bulbs.
 
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