Cloning problem

[guilty]

Here's my class:

//File: TestClass.java
public class TestClass
        implements Cloneable {

    private int[] array = {0, 0, 0};

    public TestClass(int x, int y, int z) {
        this.set(x, y, z);
    }

    public void set(int x, int y, int z) {
        this.array[0] = x;
        this.array[1] = y;
        this.array[2] = z;
    }

    public int getX() {
        return array[0];
    }

    public int getY() {
        return array[1];
    }

    public int getZ() {
        return array[2];
    }

    @Override
    public Object clone()
            throws CloneNotSupportedException {
        TestClass retVal = (TestClass) super.clone();
        retVal.set(this.array[0], this.array[1], this.array[2]);
        return retVal;
    }
}

and here's my "main":

//File Main.java
public class Main {

    public static void main(String[] args) {

        TestClass testObject1 = new TestClass(2, 4, 8);
        TestClass testObject2 = null;
        try {
            testObject2 = (TestClass) testObject1.clone();
        } catch (CloneNotSupportedException e) {}
        testObject2.set(3, 9, 27);
        System.out.println("1st object: " + testObject1.getX() + ", " + testObject1.getY() + ", " + testObject1.getZ());
        System.out.println("2nd object: " + testObject2.getX() + ", " + testObject2.getY() + ", " + testObject2.getZ());
    }
}

Output:

1st object: 3, 9, 27
2nd object: 3, 9, 27

Question:
wtf?

Wished result:

1st object: 2, 4, 8
2nd object: 3, 9, 27

I have no idea what's wrong. Well I suspect that array[n] is a reference, not an actual int, but how do I make it right? Hope I made my question clear :)

[Fubarable]

You're only doing a shallow copy of the class and instead need to do a deep copy. I'm no expert in this, so any corrections are appreciated, but I think it's something like so:

   @Override
   public Object clone() throws CloneNotSupportedException {
      TestClass retVal = (TestClass) super.clone();
    
      // make a clone of the array
      int[] cloneArray = (int[])array.clone();

      // set the cloned object's array to the cloned array.
      retVal.array = cloneArray;
      return retVal;
   }

[guilty]

I don't know why, but I thought, that I couldn't access "retVal" array, because that array is public. Turns out I can! :) Thanks.

[m00nchile]

You mean private, not public. And think about it this way, a private instance can only be accessed from the current class:

public class MyClass {
  private int bla;
  //methods, constructors...
  public void doSomething() {
    MyClass m = new MyClass();
    m.bla = 5; //well, you're still in MyClass, why shouldn't you be able to acces the field bla?
  }
}

[Singing Boyo]

Yup, you can access any variable of any instance of the class you're in. Same applies for protected, so basically, if you can access this.someField, you can access otherInstance.someField.