Create a child class object based on a parent one

Jeff Hain jeffhain at
Sun Aug 10 21:12:32 UTC 2014

>Is there a better way to do this? I can think of Unsafe.

You could define a protected copy constructor like this:
protected A(A toCopy) {
    this.x = toCopy.x;
and call it from B constructor:
public B(A toCopy) {


>Please note I cannot put an A inside B because there are instanceof 
>calls that B must isa A.
You could still put A in B, and override all methods in B to delegate to A,
but that would waste memory (but if having an interface for A, B could just
implement the interface instead of extending A, and that would work well).


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