A facility for getting the current method's name

[Sebastian Sickelmann]

Am 27.09.2011 12:35, schrieb Krystal Mok:
> Hi Behrang,
>
> This reminds me of how people were looking for a "current class literal",
> something like this:
>
> public class Foo {
>    public static void main(String[] args) {
>      // don't want to hard code "Foo.class" here
>      String name = Foo.class.getName();
>    }
> }
>
> and now that JDK7 is out, they've got a new toy that gives them exactly
> that:
>
> java.lang.invoke.MethodHandles.lookup().lookupClass()
>
> It's not mean't to be fast when used like this, though.
> The same with what you're looking for, but you've already got backtrace
> which gives you the correct semantics, just not fast enough, right?
>
> On Mon, Sep 26, 2011 at 7:31 PM, Behrang Saeedzadeh<behrangsa at gmail.com>wrote:
>
>> Sean, Mario,
>>
>> I am looking for something like JavaScript's arguments.callee.name or
>> Ruby's __method__. AFAIK, accessing the current method's name is a
>> very cheap operation in JS and Ruby while creating a stack trace is a
>> moderately expensive operation in Java.
>
> They don't seem to be expensive in JavaScript or Ruby because those
> languages didn't have fast implementations. Once they do (as the current JS
> engines and JRuby/Rubinius), this kind of reflective operations will show
> their cost.
I think that this can be done at compile-time where instead of the 
method call
a constant will be inserted into the bytecode of the class. I don't see
any dynamic resolve in here. The main problem i see is how to specify 
this in java syntax.

Just replacing the INVOKESTATIC (lets say ActualMethod.getName()) into 
an LDC
breaks the common pattern how a static Methodcall in compiled to 
bytecode. Or
are there any places in javac where such a replacement for special cases 
is already done?
And a new Keyword for just inserting the methodname is a bit to big!?
Maybe the ActualMethod.getName() should be marked with a annotation 
@Constant-Replace

If i want to check if this is feasible i would write a small 
ClassFileTransformer
that exchanges any static calls of ActualMethod.getName() to the LDC at 
loadtime.
I think this is the other place where it can be done. Unfortunately i 
don't see that this
can be done on jvm in general, cause all those other languages that are 
running
on the jvm don't need such a feature. So i think javac or some custom 
post processing
would be the best place to do this.

-- Sebastian
> Regards,
> Kris Mok