How does clone work under the hood?

Question

Clone does not call the object constructor to create a copy of the object. So what algorithm does clone use ?

I am looking for implementation details of the native

Answer 1

The Object.clone() implementation is a native method that checks that the object's class implements Cloneable, and then simply allocates a new instance and does a field-by-field shallow copy. The copying is most likely done using a memory copy - there's no need for it to do anything more fancy. (But if you really want to know, look at the OpenJDK source code.)