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Message:

Don't need a copy constructor

Posted by Bill Venners on 18 Oct 1998, 9:26 AM

> I believe that all classes should support a copy constructor:

> public void someMethod (Foo fIsaFoo) {
> Foo barIsAnotherFoo = new Foo(fIsaFoo);
> ....
> }

> At the very least, a constructor with the signature:

> public Foo (Foo fooToCopy);

> should clone the argument supplied.

While I would agree that a C++ canonical object would have
a copy constructor, the clone() method is Java's way of
accomplishing the same thing. And clone() is already a
part of the canonical object idiom.

I have a bit of material about clone() versus the copy
constructor at the end of my Inner Java chapter on
cloning:

http://www.artima.com/innerjava/webuscript/cloning.html

See the section, "Clone and the Copy Constructor."

bv

• Constructor Mukhtar Shaikh November 12, 2001 at 7:03 AM (0)
• Crippled Clone Adrian Dickin 23 Feb 1999, 7:59 AM (0)