Re: String literal
stef wrote:
IMHO the assignment of a literal to a string class (String s =
"Hello";) is... amazing for an strongly oriented object language like
Java. I mean, In opposition to C++ (for example) Java doesn't
implement that kind of constructor (operator =)
Not really. You're assigning a String literal to a... String object.
What's "amazing" is that Java doesn't treat int, etc., as subtypes of
Object, which was a really bad idea in retrospect (auto{un}boxing
mitigates this to some degree, though).
Also, the lack of an assignment operator or copy constructor can be
traced probably most closely to the fact that Java treats all objects as
if they were on the heap instead of differentiating between stack-based,
dies-on-scope-close objects and objects on the heap (or statically
initialized). With the fact that Java is more statically-typed than C++
playing a little role, too.
On the other side, it seems that String s = <literal> is treated like
a primitive assignment, but... it stills a class :)
Modern OO design tends to agree that the distinction between primitive
types and the inheritance tree is a bad one.
This "trick" has been implemented to get better performance (see
Intern() method) ?
What method would you do instead of String s = "Hello"? String s = new
String(new char[] {'S', 't', 'r', 'i', 'n', 'g'})? It's not for better
performance, it's for basic common sense. As I keep reiterating, it's
int and friends that are ultimately broken, not String.
And String.intern() is a different matter altogether whose relationship
to string literals is not its important characteristic.
--
Beware of bugs in the above code; I have only proved it correct, not
tried it. -- Donald E. Knuth