gc after for loop

[Matt DeLacey]

I've seen in a couple of mocks a question along these lines...
for (int i = 10; i >=0; i++)
{
System.out.println(i);
}
//
and then they ask you at // how many items are available for garbage collection. I always get it wrong because I say 11 (0 - 10), but the answer is always 10 and it says something about there being one instance still held somewhere. Does anybody know what I'm talking about, because I've NEVER understood that one. I think it's in the RHE mocks. ANY help at all would be appreciated.
Matt

[Prasad Ballari]

Matt,
Can you Pls explain the question indetail....Primitive data types are not under instance group...In your code you are incrementing the value of i but not creating any instances on every iteration.
Can you pls explain the question in detail.
Regards
Prasad
------------------

[Shubhangi A. Patkar]

Matt,
Could you just post an exact reference to the qustion or the question itself, it would then be much easier to solve your doubts.
Shubhangi

[mohit joshi]

There exists some very detailed discussion on this topic in earlier posts. do find them before you reinvent the wheel

[Shubhangi A. Patkar]

Originally posted by mohit joshi:
There exists some very detailed discussion on this topic in earlier posts. do find them before you reinvent the wheel

Mohit
could you please point us to the link you mean? The forum is so huge, it is giving nearly 200+ results for searchon term "garbage collection".
TIA,
Shubhangi.

[Jon Aryan]

Hi Prasad,
as u know System.out variable is a PrintStream object.
In the PrintStream's println(int) the following methods is called,
String.valueOf(int);
valueOf(int) method in the String class calls the Integer.toString(int), which creates a new String object.

So, passing the primitives to the System.out.println() method creates a String object.
Passing an Object to the System.out.println() method calls the objects
toString() method if the object reference is not null, if the object reference is null, a new String "null" is created and written to the stream.
---------------------
Hi Matt,
in the following code it looks like all the 11 objects will be
garbaged collected !.
When the output stream objects get a String object,
it will take the characters out from the String and outputs to the underlying sink ( it may use char[], or byte[] for buffering and flushes the buffer).
So y the PrintStream should hold the reference to the last Object in the for loop. rite ??
So i guess ur rite, 11 objects will be garbage collected

class Tester2 {
static int count;
static final int OBJ_COUNT = 10;
  public static void main(String args[]) {
    for (int i = 0; i <= OBJ_COUNT; i++) {
   // Assuming System.out.println(int) will create 11 String objects
      X x = new X();
      System.out.println(x);
   }
   //while(true) {
  // Exit when all the objects are garbage collected.
   while(count <= OBJ_COUNT) {
   // forcing the GC to run
    new Object();
    new Integer("1031");
    new Integer("107");
    new Integer("103");
   }
  }
}
  class X {
  static int a;
  int i;
    X() {
      a++;
      i = a;
    }
    public void finalize() {
      Tester2.count++;
      System.out.println("Finalized : " + i);
    }
    public String toString() {
      return new String(" " + i);
    }
}

Correct me if am wrong

[This message has been edited by Jon Aryan (edited November 14, 2000).]

[Matt DeLacey]

I suppose my question is, does the PrintStream hold the reference after the for loop is complete? I would think it would not, because it then goes out of scope, but the answer to the mock suggests that it does. The mock answer is 10 even though I feel that it should be 11. Strange, perhaps it's just errata.
Matt

[mohit joshi]

try this


and this

[This message has been edited by mohit joshi (edited November 14, 2000).]

[Lisa Yanchunis]

I have read most of the referenced thread from this and there are a number of interest points. However, I agree that it would be 10. Although "i" goes from 0-10 the system only prints 1-10 (the loop is exited before printing 0). Therefore there are only 10 strings created, there could never be more than 10 objects to garbage collect.
Lisa

[Matt DeLacey]

Well, actually the loop iterator ought to be i--...if it WAS...
0 WOULD be printed...not sure i see where you are coming from Lisa...sorry. Mohit, thank you very much...I followed those links...to me it seemed like there is absolutely no consensus.
Matt