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Re: looking at generic

At 12:04 pm -0700 30/10/04, Elliotte Harold <email@hidden> wrote: 

 You still *think* C++, apparently. How can "dereference a null pointer " in
 Java ?


 String s = null;
 int c = s.charAt(0);

Normally it's more subtle than that, of course.

S is not a pointer. It's a reference.

No, s is a pointer, not a reference (in the C++ sense; in Java terminology there's no difference and they're synonymous).

When people say "Java is just C++ but everything is reference and there are no pointers" what they actually mean is "Java is just like C++ but everything is a pointer, there are no references (only Java uses a different syntax from C++)".

Java takes the syntax that C++ uses for reference but uses it for pointers. Java "a.b" is C++ "a->b", Java "a[5]" is C++ "a+5". In that case, you might ask, how do you write C++ "*ptr" or "ref.a" or "a[5]" in Java? Answer, you don't, they're meaningless because Java doesn't have references!

-Rolf
--
Rolf Howarth, Square Box Systems Ltd, Stratford-upon-Avon UK.
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