String pool

[Girish Nagaraj]

Look at the following piece of code

...
...
String s1 = "Hello!";
String s2 = "Hello!";
s1 = null;
...

Totally how many objects are created and how many are eligible for garbage collection?

[Aniket Patil]

s1 and s2 both point to the same string literal. If s1 is set to null, there still exists s2 referring to the literal. So there should be none eligible.

[Rushikesh Wagh]

1 Object Gets Created
And
0 Objects Are eligiable For GC.

[Girish Nagaraj]

Where is the String object created is it in the string pool or in the heap?

[Aniket Patil]

In the String pool.

For eg:

String s = "Hello" -->Hello is dropped into the String pool and s will refer to it.

String s = new String("Hello") -->Hello is created in non-pool memory, and it is also placed in the pool.

In addition this might help you:
https://coderanch.com/t/252763/java-programmer-SCJP/certification/diffrence-heap-pool
[ May 03, 2006: Message edited by: Aniket Patil ]

[sreenivasa reddy]

when u try to instantiate a string object, it will initially search for a object in the pool with same value. if no object is found then it will create one for u and returns that object reference, if there is some object already in the pool, it will retur the reference of the same object.
so for the code u mentioned there are two reference variables pointing to one object.as, some reference is pointing to the object, no object is free, so no garbage collection.

[Sandeep Vaid]

I completely agree with Rushikesh Wagh