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Question 1) I know what happens when we make object reference variable to "null". The object is eligible for GC. because there is no more reference to it.
However , if suppose an object has instance variable. These variable also goes to "null" or it contains its value?
s ----> object_1
instance variable: k--------> object_2
what happens to "k". How many objects are eligible for GC. One or Two?
Question 2) when i make object references equal to other object reference
when i do
x2 start referencing to obj_3. I want to know , x1 will still refer to obj_3 or it lost his reference?
Because i know its x1 bytes are copying to x2 , technically x1 should not loose its object. But still in some problems i find it other way(i.e. x1 loose its object)
Saurabh Vohra wrote:The object is eligible for GC. because there is no more reference to it.
To be more precise, an object is eligible for garbage collection when there is no reachable reference to it.
So, assuming that s is the only reference to object_1 and object_1.k is the only reference to object_2, then when you set s to null, object_1.k is no longer reachable and so object_2 also becomes eligible for garbage collection.
In your second question, x1 and x2 will both refer to obj_3. If you've ever found anything different then you must have modified x1 somewhere else in your code.