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Doubt in creating strings...

thambi durai

Joined: Jan 30, 2008
Posts: 6
can any one explain the two way of String creation ...

String s="hello";
String s=new String("hello");
how many object and reference is created in heap and pool.


public String makinStrings()
String s = �Fred�;
s = s + �47�;
s = s.substring(2, 5);
s = s.toUpperCase();
return s.toString();
How many String objects will be created when this method is invoked?
A. 1
B. 2
C. 3
D. 4
E. 5
F. 6
Ian Edwards
Ranch Hand

Joined: Aug 14, 2006
Posts: 107
Okay, if we go through the code line by line:

We are creating a String object here and giving s a reference to it.

"47" is a String object, and we are creating a new string object by concatenating "47" to "Fred". We lose the reference to "Fred" and point s to "Fred47".

In this line we are creating a new String object, "ed4", and assign it to s.

Here we create a new String object, "ED4", and assign it to s.

Lastly, we create a new String object using the toString() method.

In total we are creating 6 string objects.
thambi durai

Joined: Jan 30, 2008
Posts: 6
but the answer is 3...
how it's possible..
Dean Jones
Ranch Hand

Joined: Dec 29, 2007
Posts: 129
Dear Thambi,

please see the link

Joined: Sep 20, 2007
Posts: 8
I agree. Here's the link:
subject: Doubt in creating strings...
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