Delegates?

[r035198x]

The delegates white paper say they are not neccessary. I buy most of the arguments there. However it's possible to implement them in java (That article could have been improved by using generics in the code).
The questions I have are:
1.) Does using delegates imply that the design is not fully object oriented?
2.) Which is more object oriented? Inner classes + Reflection vs Delegates

[JosAH]

The delegates white paper say they are not neccessary. I buy most of the arguments there. However it's possible to implement them in java (That article could have been improved by using generics in the code).
The questions I have are:
1.) Does using delegates imply that the design is not fully object oriented?
2.) Which is more object oriented? Inner classes + Reflection vs Delegates

None of the two buy you much over the other. A Microsoft 'delegate' simply
wraps an anonymous class thing around a method. It may allow for closures
(I have to look into that in a little more detail), but I suspect that it doesn't.
I might be wrong though.

At the least I find the name 'delegate' confusing; I'd call it a 'mimicker' or something.

kind regards,

Jos

[r035198x]

None of the two buy you much over the other. A Microsoft 'delegate' simply
wraps an anonymous class thing around a method. It may allow for closures
(I have to look into that in a little more detail), but I suspect that it doesn't.
I might be wrong though.

At the least I find the name 'delegate' confusing; I'd call it a 'mimicker' or something.

kind regards,

Jos

That's another thing about them. The name throws a bit of a cloud. I'd have thought in pure delegation, an object forwards both a request and itself to another object (as in the state pattern).

[JosAH]

That's another thing about them. The name throws a bit of a cloud. I'd have thought in pure delegation, an object forwards both a request and itself to another object (as in the state pattern).

The construct is more like a C/C++ function pointer and as we all know simple
interfaces and small (anonymous) class objects can do the same thing.

If I would've been Microsoft (god forbid!) I'd gone the whole nine yards and
implemented closures instead.

kind regards,

Jos

[odefta]

You can't use delegates in java!
The java events mechanism is different from C# for example.
I C# you declare a delegate, an event that use the delegate, a method that implements the code of event and so on...

In java you declare an event like...

import java.util.EventListener;
public interface WizardListener extends EventListener
{
public abstract void nextSelected(WizardEvent e);
public abstract void backSelected(WizardEvent e);
public abstract void cancelSelected(WizardEvent e);
public abstract void finishSelected(WizardEvent e);
}

Then implement this..and so on..

For details you can read:
http://www.javaworld.com/javaworld/j...javatip35.html

[r035198x]

You can't use delegates in java!
....

You can implement them if you want. Read my first post again.