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garbage collector......output.....?

Ganeshkumar cheekati
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Joined: Oct 13, 2008
Posts: 362
this is from esnips

Given the following code, how many objects will be eligible for garbage collection on the line with the comment //here

answer is:no object is eligible.

here two objects created for x and y.changes in method will not modify these up to now no object is eligible.

In line1 z is pointing to the object which is refered by y.
In line2 z is one object is eligible.

can you explain line1 and line2?
[ November 02, 2008: Message edited by: Ganeshkumar cheekati ]

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Vijitha Kumara

Joined: Mar 24, 2008
Posts: 3902

It's the reference you are making null. What about the y reference? Still the object (created with the value 99) is referenced by y.
[ November 02, 2008: Message edited by: Vijitha Kumara ]

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Anoobkumar Padmanabhan
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Joined: Aug 08, 2007
Posts: 103

In line1, we are doing is that, just giving a new refenrce, z, to the object referred by y. so both y and z are pointing to the same object. In line2, we are assigning the refernce, z to null. ie, only changing the refernce, z. Still, y is pointing to the object. So, this won't be available for garbage collection. So the answer will be right.

Thanks<br /> <br />Anoobkumar<br />SCJP 1.5
Ankit Garg

Joined: Aug 03, 2008
Posts: 9465

I have changed the code a little bit. When you set yy to null, it has no effect on y. So y refers to the integer object with value 99 and x refers to integer object with value 10 when the statement in question is reached.

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Ganeshkumar cheekati
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Joined: Oct 13, 2008
Posts: 362
yeah i got it .
Henry Wong

Joined: Sep 28, 2004
Posts: 20529

this is from esnips

The site being quoted is a filesharing site -- and cannot be used to validate a source. Filesharing sites do not check validity -- in fact, it has been know to share copyrighted materials.

Please do not quote from this site again -- as it will be treated as without a quote, and may have to be removed.

[ November 03, 2008: Message edited by: Henry Wong ]

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I agree. Here's the link:
subject: garbage collector......output.....?
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