I have a beginners question about java fundamentals of variable assignments.
In my example code I have 3 boxes (Objects). I assign the boxes as follows:
Box box1 = new Box("Furniture", 1);
Box box2 = new Box("Games", 2);
Box box3 = new Box("Cloths", 3);
box1 = box2;
box2 = box3;
System.out.println(box1.toString());
System.out.println(box2.toString());
Now, I would expect that box1 also points to box3. But it turns out, that it still points to box2, eventhough I also changed the reference of box2 to box3. Why is that so?
This is your initial state :
+-----------------+ +----------------+
| box1 ( ref ) +------------>| box1 ( obj ) |
+-----------------+ +----------------+
+-----------------+ +----------------+
| box2 ( ref ) +------------>| box2 ( obj ) |
+-----------------+ +----------------+
+------------------+ +----------------+
| box3 ( ref ) +----------->| box3 ( obj ) |
+------------------+ +----------------+
This is what happens after box1 = box2 :
+-----------------+ +----------------+
| box1 ( ref ) +----+ | box1 ( obj ) |
+-----------------+ | +----------------+
|
+-----------------+ +------> +----------------+
| box2 ( ref ) +------------>| box2 ( obj ) |
+-----------------+ +----------------+
+------------------+ +----------------+
| box3 ( ref ) +----------->| box3 ( obj ) |
+------------------+ +----------------+
This is what happens after box2 = box3
+-----------------+ +----------------+
| box1 ( ref ) +----+ | box1 ( obj ) |
+-----------------+ | +----------------+
|
+-----------------+ +------> +----------------+
| box2 ( ref ) +----+ | box2 ( obj ) |
+-----------------+ | +----------------+
|
+------------------+ +------->+----------------+
| box3 ( ref ) +----------->| box3 ( obj ) |
+------------------+ +----------------+
Now you should be able to figure out why the output is like that . :)