Regarding remove() and clear () method

Question

when we call clear() and remove(index) method for vector or hashtable, the element will be removed and the size decreases by one . The question is wheteher the memory will get freed when these methods are called?

Answer 1

Hi,
Vectors hold only references to other objects. Hence, when you "add or remove" elements to vectors, you are only adding or removing references to other objects in the heap.
Memory taken by objects in the heap is freed as per the whims of the garbage collector. Unless your program does some memory-intensive computation, the garbage collector might not even run during your program's execution phase.
If you have declared Vector v = new Vector();, the JRE will create a vector object in the heap, capable of storing 10 references. If you try to add an 11th reference to the vector, the Vector object will grow automatically by a default increment. Since in your code you are adding and removing references continuously, the Vector size will remain the same as long as the number of references never exceeds 10.
Regards,
Kumar.