JavaException when calling Java methods stored in Python class variables

[JoshRosen]

I ran across a confusing JavaException when trying to call a Java method stored in a class variable:

from jnius import autoclass                                                     

System = autoclass('java.lang.System')                                          

# This works:                                                                   
System.out.println('Hello World')                                               
map(System.out.println, ['Hello World'])                                        
println = System.out.println                                                    
map(println, ['Hello World'])                                                   

class MyClass(object):                                                          
    def __init__(self):                                                         
        self.println = System.out.println  # Instance variables are fine                                      
map(MyClass().println, ['Hello World'])                                         

# This causes an exception:                                                                 
class MyClass(object):                                                          
    println = System.out.println  # But class variables cause errors                                          
map(MyClass.println, ['Hello World'])

Running this code produces the following output:

Hello World
Hello World
Hello World
Hello World
Traceback (most recent call last):
  File "jniustest.py", line 19, in <module>
    map(MyClass.println, ['Hello World'])
  File "jnius_export_class.pxi", line 745, in jnius.JavaMultipleMethod.__call__ (jnius/jnius.c:15502)
jnius.JavaException: No methods matching your arguments

This is an odd edge-case with an easy workaround (don't store Java methods in class variables), but I thought I'd report it here in case anyone else encounters it.

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