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anyone saw this on code?

anyone saw this on code?# Java - 爪哇娇娃

I*o2008-09-05 07:09

1 楼

public class C
{
public static final String A = C.A;
...
}
what's point of this...

g*g2008-09-05 07:09

2 楼

I don't know, I would use
import static C;
if it's for shorten name.

【在 I*******o 的大作中提到】

: public class C
: {
: public static final String A = C.A;
: ...
: }
: what's point of this...

A*o2008-09-05 07:09

3 楼

does it compile and does it work?
very interesting static hell.

【在 I*******o 的大作中提到】

: public class C
: {
: public static final String A = C.A;
: ...
: }
: what's point of this...

s*e2008-09-05 07:09

4 楼

It's the same as A = A; or probably A = null; (how could we be sure???)
as a static final field, it has to be initialized when the class is loaded.
but i don't like such tricky thing.

【在 I*******o 的大作中提到】

: public class C
: {
: public static final String A = C.A;
: ...
: }
: what's point of this...

Z*e2008-09-05 07:09

5 楼

don't see the point, it's functionally equivalent to
public static final String A = null;

【在 I*******o 的大作中提到】

: public class C
: {
: public static final String A = C.A;
: ...
: }
: what's point of this...

b*y2008-09-05 07:09

6 楼

不清楚

I*o2008-09-05 07:09

7 楼

i saw this crap from someone's code when i was fixing a bug
it compiles!!

【在 A**o 的大作中提到】

: does it compile and does it work?
: very interesting static hell.

Z*e2008-09-05 07:09

8 楼

it's a valid statement, but meaningless

【在 I*******o 的大作中提到】

: i saw this crap from someone's code when i was fixing a bug
: it compiles!!

A*o2008-09-05 07:09

9 楼

haha, happy reading. :)
in that case, find the most senior or the most knowledgable employee
to find out if there is any story behind it.

【在 I*******o 的大作中提到】

: i saw this crap from someone's code when i was fixing a bug
: it compiles!!

I*o2008-09-05 07:09

10 楼

holly.... i was first surprised it complied!
maybe it's intended to be used as a placeholder.

【在 A**o 的大作中提到】

: haha, happy reading. :)
: in that case, find the most senior or the most knowledgable employee
: to find out if there is any story behind it.

Z*e2008-09-05 07:09

11 楼

here's my understanding:
variables on stack must be intialized; that's why if you define a variable
in a routine, and try to use it without initializing it, you'll get a
compiler error
variables on heap, like class variables, are preinitialized with null/0/
false when the memory space for the class is allocated; that's why you can
make reference to it even without initializing it. so when compiler sees
that statement, it will just try to assign the preinitialized value of A to
A again, which is

【在 I*******o 的大作中提到】

: holly.... i was first surprised it complied!
: maybe it's intended to be used as a placeholder.

S*t2008-09-05 07:09

12 楼

it is defined final.
so this code is doing nothing and it is confusing people, which should be
avoided.

to

【在 Z****e 的大作中提到】

: here's my understanding:
: variables on stack must be intialized; that's why if you define a variable
: in a routine, and try to use it without initializing it, you'll get a
: compiler error
: variables on heap, like class variables, are preinitialized with null/0/
: false when the memory space for the class is allocated; that's why you can
: make reference to it even without initializing it. so when compiler sees
: that statement, it will just try to assign the preinitialized value of A to
: A again, which is

Z*e2008-09-05 07:09

13 楼

with or without final, the line of code is doing nothing; adding a final
further rendered the vairable uselss because it can no longer be assigned to
any other value

【在 S*********t 的大作中提到】

: it is defined final.
: so this code is doing nothing and it is confusing people, which should be
: avoided.
:
: to