克隆列表并将元素的属性修改为list在Java中不起作用

import java.util.ArrayList;
import java.util.List;

class Element implements Cloneable {
    private String attribute;

    public Element(String attribute) {
        this.attribute = attribute;
    }

    public String getAttribute() {
        return attribute;
    }

    public void setAttribute(String attribute) {
        this.attribute = attribute;
    }

    @Override
    protected Element clone() throws CloneNotSupportedException {
        return (Element) super.clone();
    }
}

public class Main {
    public static void main(String[] args) {
        List<Element> originalList = new ArrayList<>();
        originalList.add(new Element("attribute1"));
        originalList.add(new Element("attribute2"));

        List<Element> clonedList = new ArrayList<>();
        for (Element element : originalList) {
            try {
                clonedList.add(element.clone());
            } catch (CloneNotSupportedException e) {
                e.printStackTrace();
            }
        }

        // 修改克隆列表中元素的属性
        for (Element element : clonedList) {
            element.setAttribute("modified");
        }

        // 输出原始列表和克隆列表的元素属性
        System.out.println("Original List:");
        for (Element element : originalList) {
            System.out.println(element.getAttribute());
        }

        System.out.println("Cloned List:");
        for (Element element : clonedList) {
            System.out.println(element.getAttribute());
        }
    }
}