Far classes

[Thomas Schatzl]

On 18.06.24 14:23, Thomas Stüfe wrote:
 > Hi,
 >
[...]
 >
 > So: 3) Store Klass* in the object:
 >
 > We dedicate one bit in the nKlass for "is-far-class". For far classes,
 > we store the Klass* at the end of the object. Then we encode the offset
 > of the Klass* slot in the remaining nKlass bits.
 >
 > That depends on max. object size. How large does an object get? I found
 > no limit in specs. However, the size of an object depends on its
 > members, and we have an utf-8 CP-entry per member, and the number of CP
 > entries is limited to 2^16. So, an object cannot have more than 65535
 > members (a bit less, actually). Therefore, I think it cannot be larger
 > than 64k heap words.

A child class of a class with 64k members can have 64k members again 
afair. Not sure if there is a limit on the inheritance level. I remember 
some tests constructing such huge objects for testing some GC algorithms.

So j.l.O. instances can be of "arbitrary" size afaik.

Hth,
   Thomas