package org.python.core;
import org.python.expose.ExposedGet;
import org.python.expose.ExposedMethod;
import org.python.expose.ExposedNew;
import org.python.expose.ExposedType;
/**
* The classmethod descriptor.
*/
@ExposedType(name = "classmethod", doc = BuiltinDocs.classmethod_doc)
public class PyClassMethod extends PyObject implements Traverseproc {
public static final PyType TYPE = PyType.fromClass(PyClassMethod.class);
@ExposedGet(name = "__func__")
protected PyObject callable;
public PyClassMethod(PyObject callable) {
if (!callable.isCallable()) {
throw Py.TypeError("'" + callable.getType().fastGetName() + "' object is not callable");
}
this.callable = callable;
}
@ExposedNew
final static PyObject classmethod_new(PyNewWrapper new_, boolean init, PyType subtype,
PyObject[] args, String[] keywords) {
if (keywords.length != 0) {
throw Py.TypeError("classmethod does not accept keyword arguments");
}
if (args.length != 1) {
throw Py.TypeError("classmethod expected 1 argument, got " + args.length);
}
return new PyClassMethod(args[0]);
}
public PyObject __get__(PyObject obj) {
return classmethod___get__(obj, null);
}
public PyObject __get__(PyObject obj, PyObject type) {
return classmethod___get__(obj, type);
}
@ExposedMethod(defaults = "null", doc = BuiltinDocs.classmethod___get___doc)
final PyObject classmethod___get__(PyObject obj, PyObject type) {
if(type == null) {
type = obj.getType();
}
return new PyMethod(callable, type, type.getType());
}
/* Traverseproc implementation */
@Override
public int traverse(Visitproc visit, Object arg) {
return callable != null ? visit.visit(callable, arg) : 0;
}
@Override
public boolean refersDirectlyTo(PyObject ob) {
return ob != null && ob == callable;
}
}