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From: j4n bur53 <janburse@fastmail.fm>
Newsgroups: comp.lang.java.programmer
Subject: Re: Are Outer Classes Loaded Lazily?
Date: Thu, 21 Sep 2017 01:18:12 +0200
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for nested classes the method getEnclosingClass(),
calls getDeclaringClass(), which is native. but I
guess it will use the outer_class_info_index in
the class file format.

which is a little unnecessary, since it could derive
the outer class name from the inner class name,
lastIndexOf('$') or somesuch.

but your testing somehow indicates that getDeclaringClass()
indeed works lazily. Can this be? This would imply
that it can be possible that the static of Inner

might be called before the static of Outer?

Or is this an artefact of reflection. Since in
real code we habe a name Outer.Inner and since
this mentions Outer, it would load Outer?

Eric Sosman schrieb:
> On 9/20/2017 1:23 PM, j4n bur53 wrote:
>> Assume I have a nested inner class Inner,
>> and I do the following:
>>
>>     Class x=Class.forName('../Outer$Inner');
>
>     One or two tiny little problems here ... ;)
>
>> And then I do the following:
>>
>>     Class y=x.getEnclosingClass();
>>
>> Is the enclosing class '../Outer' already
>> loaded during the Class.forName() or only
>> when I do getEnclosingClass() ?
>
>     You'd need to scrutinize the JLS and/or the JVMS to be
> certain.  That can be difficult: They seek exactness and
> sometimes find it on the other side of opacity ...
>
>     Instead, I ran a quick experiment: I wrote suitable
> Outer and Inner classes, plus a Foo class to make the
> forName() and getEnclosingClass() calls sandwiched by
> some System.out.println() calls, and ran it as
>
>     java -verbose:class esosman.misc.Foo
>
> This told me that forName() caused Inner to be loaded
> but not Outer, and that getEnclosingClass() caused
> Outer to be loaded but not initialized.  (I also found
> that Inner was initialized during forName() if it was
> made `static', but couldn't tell what happened when it
> was non-`static'.)
>