Re: Question on vectors?

I overrode the equals method, it works now thanks all.

Ron Power
Programmer
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709-576-8132
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http://www.stjohns.ca/
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Re: Question on vectors?






Ron,

I'm not quite sure what your last "if" statement was. It was garbled by my 

Notes mail reader: 
if 
((vector2.indexOf((BulkGarbageSchedDetail)vector.get(i)))<0){
                                        result = false;
                                }
But I'm guessing that your feeling about overriding equals is right. You 
will need to create some custom code to distinguish between the elements 
in the list. You will need to identify one or a group of key attributes 
that would always distinguish one element instance from another. The 
question is what to override. Do you really need to use a Vector? Vectors 
are somewhat deprecated, as they have thread-safe synchronization built 
into them, and can thus be slow in some circumstances. The List family of 
collections is usually preferred. But do you want an ordered List or an 
unordered List? There might be some advantage in having your elements 
automatically sorted as they are inserted, or checked for uniqueness, but 
that's up to you.

Anyway, what it comes down to is, do you override Object.equals, or create 

a Comparator class? Use the Comparator class if you are ever going to sort 

your collection. If not, then override Object.equals. But if you do go the 

Object.equals route, make sure to override Object.hashCode as well. Your 
elements may get stored in a hash table, either by your code or some 
library code. Hash tables are used by almost everything, even Properties. 
Unless you have also overridden hashTable, you may have some weird 
behavior to try and figure out.

Good luck!
_________________________________________________________________
Jeff Furgal / MIMIX Product Architect / Lakeview Technology

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