JDK-8057919 Class.getSimpleName() should work for non-JLS compliant class names

[Vladimir Ivanov]

Jochen,

Let me elaborate on that topic a bit.

There are 5 types of classes mentioned in JVMS:
   - top-level
   - nested
   - inner
   - local
   - anonymous

Example:
class TopLevel {
   static class Nested {}
   class        Inner  {}

   void f() {
     class Local {}
   }
   Object o = new TopLevel() {}; // anonymous
}

And here's how they look like on bytecode level.

I'll use both javap and ASM to dump class structure:
   $ java jdk.internal.org.objectweb.asm.util.ASMifier <class_file>

Nested:
   javap: static #11= #10 of #5; //Nested=class TopLevel$Nested of class 
TopLevel
   asm: cw.visitInnerClass("TopLevel$Nested", "TopLevel", "Nested", 
ACC_STATIC);

Inner:
   javap: #8= #7 of #5; //Inner=class TopLevel$Inner of class TopLevel
   asm: cw.visitInnerClass("TopLevel$Inner", "TopLevel", "Inner", 0);

Local:
   javap: #13= #12; //Local=class TopLevel$1Local
   asm: cw.visitInnerClass("TopLevel$1Local", null, "Local", 0);

Anonymous:
   javap: #2; //class TopLevel$1
   asm: cw.visitInnerClass("TopLevel$1", null, null, 0);

TopLevel.class contains all aforementioned attributes.

Best regards,
Vladimir Ivanov

On 6/16/15 7:29 AM, Jochen Theodorou wrote:
> Am 15.06.2015 18:04, schrieb Vladimir Ivanov:
> [...]
>> In order to make the class non-anonymous again, you have to specify
>> inner_name_index and, optionally, outer_class_info_index.
>
> ok... let me try to understand this better... taking this Java source
>
>> public class Test {
>> public static void main(String[] args) {
>>   class X{}
>>   Runnable foo = new Runnable(){public void run(){}};
>> }}
>
> I get for Test
>
>> InnerClasses:
>>      static #2; //class Test$1
>>      #12= #11; //X=class Test$1X
>
> Is it the #12=#11 part which tells me X is no anonymous class? Is #11
> the inner_name_index?
>
> bye Jochen
>