Am 13.03.2012 11:11, schrieb Invisible:

> The real sticking point was when I started trying to use abstract
> classes. It seems that you cannot have a variable of an abstract class.
> (Because creating that variable would require creating an instance of an
> abstract class, which is illegal.) You can only have a variable that
> /points to/ such a value. (Because then what it points to can actually
> be some concrete subclass.)
>
> That's all fine and logical and everything, but there's a nasty snag:
> Now you have to care about memory management. And there's no way around it.

Forget all you know about classic C pointers; instead, try the C++11 
(aka C++0x) shared pointers - they'll take care of all the disposing 
stuff. (If C++0x is not an option, use the boost library; C++0x took 
them right from there).

Instead of e.g.

     MyVirtualClass* o1 = new MySubClass(...);
     MyVirtualClass* o2 = o1;
     o1->doThis();
     o2->doThat();
     dispose o2; o1 = null; o2 = null;

you'd write

     shared_ptr<MyVirtualClass> o1(new MySubClass(...));
     shared_ptr<MyVirtualClass> o2(o1);
     o1->doThis();
     o2->doThat();
     o1 = null;
     o2 = null;

Note that the dispose is gone for good. Shared pointers use reference 
counters to accomplish this feat.

To save you some typing, you may want to use

     typedef shared_ptr<MyVirtualClass> MyVirtualClassPtr;

(Caveat: Assignments of shared pointers are a little tricky, as the 
assignment operator "o1 = o2;" is actually implemented as a swap 
operation; you'll need to use "o1 = shared_ptr<MyVirtualClass>(o2);" 
instead to clone a pointer.)

There is also a complementary weak_ptr, which allows the referenced 
object to be destroyed. To try to access the object, get a shared_ptr 
from the weak_ptr, verify that the shared_ptr is non-null and access the 
object.

> Like VS, asking NetBeans for a basic project generates a plateful of
> useless code that you then have to waste time deleting. (Apparently
> there's an Ant script somewhere too... whatever the hell that is.) It
> also sets the tab depth far, far too deep. But unlike VS, it also seems
> to /insist/ on incorrectly putting the open bracket on the same line as
> the declaration it begins. (This incorrect practise is also common in
> C++, and yet I didn't seem to have this problem with VS.) It's easy
> enough to manually fix, I suppose.

There's nothing "incorrect" about that way of placing braces, even in 
C++. It's syntactically correct, so say what you will.

As for Java, it's actually /the/ official curly braces convention, as 
recommended by Sun and later Oracle.

> So there we are. I doubt I'd remember much about the AWT (although,
> didn't they deprecate that in favour of Swing?),

The JAVA API has a rich history of deprecating interfaces, deprecating 
interfaces designed to replace deprecated interfaces, and un-deprecating 
deprecated interfaces. I wouldn't be surprised if AWT was among the latter.

> but I can certainly
> still write algorithmic code in Java without much ado. Maybe today I'll
> try something more ambitious with it. If I can avoid throwing the IDE
> out of a window.

Try Eclipse. Somehow it seems to be the unofficial standard IDE. (Never 
tried it myself in depth though; it has that very special 
Open-Software-Project air about it that somehow makes my skin crawl ever 
since I tried OpenOffice for real.)

> (Is it just me? "Net Beans"? It's an IDE. What the /hell/ does that have
> to do with networking? The "beans" part I kinda get; everything
> Java-related has to be themed on coffee or coffee beans. But why "net"?)

Maybe because "The NetBeans project consists of an open-source IDE and 
an application platform that enable developers to rapidly create web, 
enterprise, desktop, and mobile applications using the Java platform [...]"?


Anyway, I personally stick to IDEs developed by software development 
companies (and I mean companies that develop other stuff besides 
programming languages and IDEs). So far the best IDE experience has been 
Visual Studio for C#. One might snarl at the company's marketing 
strategies, but they seem to know what helps software developers to be 
productive.

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