number of objects created?

[srikanth reddy]

hi ,

String x=new String("xyz");
y="abc";
x=x+y;

how many string objects are created???


thanks & regards

srikanth reddy

[Marcelo Ortega]

4 String objects are created.

[Stephen O'Kane]

what are the four string objects?

one for x
one for y
one for storing an intermediate value?
one for storing the final value of x?

thanks
Sok

[Joji Doi]

String x=new String("xyz"); // two objects are created. xyz and new String
y="abc"; // one object is created. abc
x=x+y; // one object is created abcxyz

Total of four objects are created unless xyz and/or abc are already in the constant pool.

[Vijay Gade]

String x=new String("xyz"); // two objects are created. xyz and new String

This is real news to me. I thought only one object is created. But my question is, if

new String ("xyz"

) creates two objects, (where one is a new String(), and the other is "xyz"), then how can the reference x (as in String x) point to two objects (new String() and "xyz" at the same time?

Thanks,

-Vijay

[Vijay Gade]

Hi,

Got the answer to that one.

String x = new String ("xyz");

is equivalant to

char data[] = {'x', 'y', 'z'}; //--> Array Object #1
String x = new String (data); //--> String Object #2

That's two objects.

Thanks,

-Vijay

[Dinesh Kodiyat]

That was realy interesting one!.Thanks

[Steve Morrow]

Hi,

Got the answer to that one.

String x = new String ("xyz");

is equivalant to

char data[] = {'x', 'y', 'z'}; //--> Array Object #1
String x = new String (data); //--> String Object #2

That's two objects.

That's not quite how it works. The original line of code contains a String literal. When the class is loaded, a String object is created on the heap based on the character sequence "xyz", and a reference to this String is retained in a pool. When the method containing this line is run, a new String is created on the heap, containing the same character sequence as the previously created String object. After this code executes, there are two Strings on the heap, each containing the character sequence "xyz".

If you compare the object references with x == "xyz", you'll find it returns false, meaning the references point to different objects.

In practical code, lines such as the one above (new String("whatever"))are impractical and wasteful, as they create unnecessary String objects. It's useful for testing purposes, however, to know what's going on, and that such a line results in two separate String objects.

Hope this helps!

[Vijay Gade]

Hello Steve,

Thank you very much. I guess I'm the third kind of the guy who cannot count!

-Vijay