I'm trying to use custom class implementing Set and Comparable interface in Jython but have the following error :
Exception in thread "main" TypeError: Supertypes that share a modified attribute have an MRO conflict[attribute=__le__, supertypes=[<type 'java.util.Set'>], type=Scratch$MyCollection]
I am using java temurin 21.0.6 and jython-standalone 2.7.4.
I prepared a simple code example to reproduce :
public static void main(String[] args) {
try (PythonInterpreter interpreter = new PythonInterpreter()) {
interpreter.set("c", new MyCollection());
}
}(Please note that you can just use Py.java2py(new MyCollection()) and will achieve the same result)
Where MyCollection is a basic implementation :
private static class MyCollection implements Set, Comparable {
@Override
public int compareTo(@NotNull Object o) {
return 0;
}
@Override
public int size() {
return 0;
}
@Override
public boolean isEmpty() {
return false;
}
@Override
public boolean contains(Object o) {
return false;
}
@Override
public @NotNull Iterator iterator() {
return null;
}
@Override
public @NotNull Object[] toArray() {
return new Object[0];
}
@Override
public boolean add(Object o) {
return false;
}
@Override
public boolean remove(Object o) {
return false;
}
@Override
public boolean addAll(@NotNull Collection c) {
return false;
}
@Override
public void clear() {
}
@Override
public boolean removeAll(@NotNull Collection c) {
return false;
}
@Override
public boolean retainAll(@NotNull Collection c) {
return false;
}
@Override
public boolean containsAll(@NotNull Collection c) {
return false;
}
@Override
public @NotNull Object[] toArray(@NotNull Object[] a) {
return new Object[0];
}
}Also, I tried in previous version 2.7.3 to 2.7.0 this even simpler code and has a similar error yet not the same :
public static void main(String[] args) {
try (PythonInterpreter interpreter = new PythonInterpreter()) {
interpreter.set("c", new TreeSet<>());
}
}Exception in thread "main" TypeError: Supertypes that share a modified attribute have an MRO conflict[attribute=remove, supertypes=[<type 'java.util.SequencedSet'>, <type 'java.util.Set'>], type=SortedSet]
I tried to look a bit into it but failed to grasp exactly what is wrong, I feel like the PyJavaType.bases field is the key here, it's an array and from what I see, the order of the element inside it determine if the MRO will crash or not.
I'm trying to use custom class implementing Set and Comparable interface in Jython but have the following error :
Exception in thread "main" TypeError: Supertypes that share a modified attribute have an MRO conflict[attribute=__le__, supertypes=[<type 'java.util.Set'>], type=Scratch$MyCollection]I am using java temurin 21.0.6 and jython-standalone 2.7.4.
I prepared a simple code example to reproduce :
(Please note that you can just use
Py.java2py(new MyCollection())and will achieve the same result)Where MyCollection is a basic implementation :
Also, I tried in previous version 2.7.3 to 2.7.0 this even simpler code and has a similar error yet not the same :
Exception in thread "main" TypeError: Supertypes that share a modified attribute have an MRO conflict[attribute=remove, supertypes=[<type 'java.util.SequencedSet'>, <type 'java.util.Set'>], type=SortedSet]I tried to look a bit into it but failed to grasp exactly what is wrong, I feel like the PyJavaType.bases field is the key here, it's an array and from what I see, the order of the element inside it determine if the MRO will crash or not.