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Inheriting methods from Java in PythonJavaClass

See original GitHub issue

How do I inherit fields and methods from a Java parent class into a PythonJavaClass?

Consider the following Java base class:

package org.jnius;
public abstract class AbstractParent {
    int value=0;
    protected AbstractParent(){}
    public void doOne() { value = 1; }
    public abstract void doTwo();
class TestAbstract(with_metaclass(MetaJavaClass, PythonJavaClass)):
            __javaclass__ = 'org/jnius/AbstractParent'
            __javainterfaces__ = []
            def doTwo(self):

I can call doTwo(), but I cannot access doOne() from Python, nor value, i.e. neither of the following two statements work:

value = JavaField('()I;', static=False)
doOne = JavaMethod('()Z')

Moreover, we can’t mix Python classes that are children of PythonJavaClass and JavaClass.

It seems that PythonJavaClass (c.f. resolve_fields() in jnius_export_class.pxi) only examines self.__class__.__dict__ to find methods to add to the proxy class, while I could contend that, similar to autoclass(), it should walk the interfaces and superclasses.

Issue Analytics

  • State:closed
  • Created 4 years ago
  • Comments:5 (3 by maintainers)

github_iconTop GitHub Comments

tshirtmancommented, Apr 19, 2020

i think that was solved by your doc update PR, closing, let me know if you feel more is needed.

xloemcommented, Aug 23, 2022

@tshirtman android now provides for loading dex classes at runtime, which can be used to subclass java classes at runtime. beeware is pursuing this. ref:

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