Accessing non-public fields with bytecode about kryo HOT 3 CLOSED

From [email protected] on October 09, 2010 19:49:34

This seems like a good improvement. I will get to it eventually, thanks!

Status: Accepted

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From [email protected] on October 09, 2010 19:50:31

(No comment was entered for this change.)

Labels: -Type-Defect Type-Enhancement

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From [email protected] on February 09, 2011 00:48:55

For your idea to work, the class which accesses protected or default access members must be defined by the same classloader as the class it is accessing. Spec excerpt:

5.3 Creation and Loading
...
At run time, a class or interface is determined not by its name alone, but by a pair: its fully qualified name and its defining class loader. Each such class or interface belongs to a single runtime package. The runtime package of a class or interface is determined by the package name and defining class loader of the class or interface.
5.4.4 Access Control
...
A field or method R is accessible to a class or interface D if and only if any of the following conditions is true:

• ...
• R is either protected or package private (that is, neither public nor protected nor private), and is declared by a class in the same runtime package as D.

I implemented a workaround in ReflectASM:
http://code.google.com/p/reflectasm/source/detail?r=14

I attempt reflection and setAccessible to call the protected defineClass in the correct classloader. If this fails, ReflectASM's classloader is used. If it succeeds, then protected and default access methods and fields are accessible.

Status: Fixed

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