Please Answer soon with explanation

[Sabber bhatia]

hello there!
Please Explain

if(" String ".trim() == "String")
System.out.println("Equal");
else
System.out.println("Not Equal");

Answers
1.the code will compile an print "Equal".
2.the code will compile an print "Not Equal".
3.the code will cause a compiler error

[Keith Lynn]

According to the source of String, if there is white space in the String that you call trim on, it will return the output of the substring method. The substring method creates a new String unless the parameters to it are 0 and the length of the String.

[Sabber bhatia]

hey keith

thanks for reply but i do not get exactly wat u want to say
so please make it more clear


Sabber Bhatia

[Barry Gaunt]

Have you entered the code into a program and tested it?

[Ulf Dittmer]

Well, what output did you get when you ran it, and why do you think that is?

[Barry Gaunt]

Also read the API for the String.trim() method.
[ June 27, 2006: Message edited by: Barry Gaunt ]

[wise owen]

String Literal Pool is a very good article for String topic.

[Srikanth Kowtha]

hello there!
Please Explain

if(" String ".trim() == "String")
System.out.println("Equal");
else
System.out.println("Not Equal");

Answers
1. the code will compile an print "Equal".
2. the code will compile an print "Not Equal".
3. the code will cause a compiler error


The answer is 2.
When you compare two string objects with a "==", thats means you are comparing the object references. and definitely they are not equal.
the answer would have been 1, if the condition was
if(" String ".trim().equals("String"))

[tapan saha]

More over:


Case 1:

if("String".trim() == "String") // with-out space
System.out.println("Equal");
else
System.out.println("Not Equal");


For this ,it will refer same object for that output will be "Equal".

Case 2:

if("String ".trim() == "String") // with space
System.out.println("Equal");
else
System.out.println("Not Equal");


For this ,it will create new object for that output will be "Not Equal".

Case 3: (added by Srikanth Kowtha )

if(" String ".trim().equals("String")) // string compare
System.out.println("Equal");
else
System.out.println("Not Equal");


For this, string compare for that output will be "Equal".

[Pinkal Patel]

if(" String ".trim() == "String")
System.out.println("Equal");
else
System.out.println("Not Equal");


If you used


if("String".trim() == "String")
System.out.println("Equal");
else
System.out.println("Not Equal");


Than it will return Option 1)

will compile and o/p Equal

[wise owen]

"String".trim() will return the origianl reference. The "String" String object is in String literal pool.