[jgap-users] Follow-up re: Cloning

[Johnathan K. <jk...@rs...>]

After a little bit more digging I discovered a name for what I'm looking to
do:  A deep copy of the Chromosome.  The typical clone method only returns a
shallow copy of the object.  Apparently there are ways to implement a deep
copy on a complex object, but the methods are frequently slow.  A quick
search turned up a couple of interesting web pages:
 
http://javatechniques.com/public/java/docs/basics/faster-deep-copy.html
 
and also the following (taken from
http://forum.java.sun.com/thread.jsp?thread=474281
<http://forum.java.sun.com/thread.jsp?thread=474281&forum=54&message=2197444
> &forum=54&message=2197444):
 
 
Thanks for the suggestion to use object serialization. However, this
technique will undoubtedly prove far too slow for my needs.

I've come up with a way to deep copy using cloning. I'm sure it's
substantially faster than serialiazation although the code seems somewhat
unwieldy. Does anyone have a cleaner yet reasonably fast way of doing this?



    public Object clone() {


        


        try {           


            ClassA copy = (ClassA)super.clone();           


            copy.array = (ClassB[][])array.clone();           


            for (int i = 0; i < copy.array.length; i++) {                


               copy.array[i] = (ClassB[])copy.array[i].clone();



               for (int j = 0; j < copy.array[i].length; j++) {


                   copy.array[i][j] = (ClassB)copy.array[i][j].clone();


               }              


            }           


            return copy;           


        }


        catch (CloneNotSupportedException e) {


            return new InternalError(e.toString());


        }       


    }

Thanks,
John C.
 
 
I guess I was hoping that there was an existing deep-copy method for the
Chromosome, but I'm now guessing probably not.
 
Cheers,
 
JK