Java help

Hewin · 04-09-2003, 12:48 PM

I've looked through the API but not found anything

I'm trying to find out if there is a way to sort a vector of objects on a field in that object.
Are there any methods to do this or do I have to write one?

Hewin · 04-09-2003, 03:31 PM

I found a solution... if anyone else is interested....

make the class that the vector holds implement Comparable.

then create the following method in that class

public int compareTo(Object o){
CLASSNAME that = (CLASSNAME)o;
return this.FIELDNAME.compareTo(that.FIELDNAME;
}

Then you can call:

Collections.sort(vector);

(Dont forget to to import java.util.Collections)

this should sort it!

Tinkster · 04-09-2003, 03:32 PM

From my understanding in Java
vector implements List, which can be
sorted. All you'd have to do is make
the objects in your vector to be
comparable by the field you want
to sort them by?

Cheers,
Tink

Hewin · 04-09-2003, 03:33 PM

lol

thanks anyway tink!

Tinkster · 04-09-2003, 04:46 PM

Heh ... we had finished our posts at about the same time ...
sorry mate :}

Cheers,
Tink

acjt · 04-10-2003, 02:56 AM

You've solved your problem, however I notice you are using a Vector, are you sure you really need a vector? These objects are (the last I knew) on their way out of the api. You should look at ArrayLists and other objects in the collections api. Just thought I'd poke my nose in!