Re: How to make a class an alias of another one?

Mark Space wrote:
public abstract class ClassA {
// your methods here

public static ClassA getInstance() {
return new Temporary()
}
}

class Temporary extends ClassA {
private String temp;

// implement ClassA methods

}

Now you can declare everything as ClassA and switch implementations when you need easily. Note the lack of "public" on Temporary. It should be in the same package as ClassA.

This gives the appearance of an antipattern: one should not hardcode subclasses into their parent classes.

What safety there is in this use lies in that 'Temporary' is package-private. This isn't completely safe, in that other subclasses of 'A' can do Bad Things.

--
Lew
.

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