Shallow copy then deep copy : Clone « Class Definition « Java Tutorial

1. Java Tutorial
2. Class Definition
3. Clone

class A {
  int l = 1;
}

class B extends A implements Cloneable {
  int m = 2;
}

class CloneDemo4 extends B {
  int n = 3;
  A a = new A();

  public static void main(String[] args) throws CloneNotSupportedException {
    CloneDemo4 c = new CloneDemo4();
    CloneDemo4 c2 = (CloneDemo4) c.clone();

    System.out.println(c.l);
    System.out.println(c2.l);
    System.out.println(c.m);
    System.out.println(c2.m);
    System.out.println(c.n);
    System.out.println(c2.n);

    System.out.println(c.a == c2.a);
  }

  protected Object clone() throws CloneNotSupportedException {
    // First, perform a shallow copy.

    CloneDemo4 temp = (CloneDemo4) super.clone();

    if (a != null)
      temp.a = new A();

    return temp;
  }
}