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I CONFUSED

Martina Shahjee
Greenhorn

Joined: Sep 09, 2001
Posts: 3
RHE Second Chapter Test Yourself Q.No.5.
Which of the following code fragment would compile and print "Equal" when run(Choose one or more)
A. int x=100; Float y=100.0F; if(x==y){System.out.println("Equal");}
B. int x=100; Integer y = new Integer(100);if(x==y){System.out.println("Equal");}
C. Integer x = new Integer(100); Integer y = new Integer(100);
if(x==y){System.out.println("Equal");}
D. String x = new String("100"); String y = new String("100);
if(x==y){System.out.println("Equal");}
E. String x="100"; String y="100"; if(x==y){System.out.println("Equal");}
The Answers are A & E.
I agree with A but not with E. Since in E x and y are object ref. and will always give false when compared with == op. but here it is true since the java makes one copy of 100 and both x and y points to it.
Please give a good reason of this.
Thanks
Martina Shahjee
Gurpreet Sachdeva
Ranch Hand

Joined: Feb 20, 2001
Posts: 90
Hello Martina,
Both A and E are correct. E is correct because the strings are created from pool(not using new).
Note: When Both strings are created without using new then == operator will compare only contents of two strings.Remember I said BOTH.
Regards
Gurpreet Sachdeva
For Mock Exams, FAQ and some useful information about Bitshift operator, inner classes, garbage collection,etc please visit: http://www.go4java.20m.com
[This message has been edited by Gurpreet Sachdeva (edited September 10, 2001).]


Regards<BR>Gurpreet Sachdeva<P>For Mock Exams, FAQ, Exam tips and some useful information about Bitshift operator, inner classes, garbage collection,etc please visit: <A HREF="http://www.go4java.lookscool.com" TARGET=_blank rel="nofollow">http://www.go4java.lookscool.com</A>
 
I agree. Here's the link: http://ej-technologies/jprofiler - if it wasn't for jprofiler, we would need to run our stuff on 16 servers instead of 3.
 
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I CONFUSED
please help me out wityh this program
Why not Equal?
Can anyone explain what is == and equal( ) ?
Confused big time