Free Object-oriented basics lessonsObject-oriented basics · Stage 0 · Objects and references · Step 1
Classes, objects and references
The difference between a class and an object, what a variable really holds, and why == and equals are not the same. About 13 minutes.
Point a = new Point(1, 2); Point b = a; a = null; What is b?
- AStill the Point object: only a's reference was cleared
- Bnull, since it was the same object
- CIt throws an exception
Show the answer
Still the Point object: only a's reference was cleared. Setting a to null removes one arrow; b's arrow still points at the object.
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