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equals() question required

 
Ranch Hand
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Given that b and c refer to instances of wrapper classes, which two statements are
true? (Choose two)
A. b.equals(b) returns true.
B. b.equals(c) returns the same result as b == c.
C. b.eqials(c) can return false even if c.equals(b) returns true.
D. b.equals(c) throws an exception if b and c are different wrapper types.
E. b.equals(c) returns false if the type of wrapper objects being compared are different.
Answer: B, C
But I belive the right answer is :A,E.
Do you follow me ?
Thanks !!
 
Ranch Hand
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Hi,

I also think A,E. Please verify the question once again.
 
Sheriff
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Android IntelliJ IDE Java
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hmmm its been awhile since I've played with wrappers... so I wrote a bit of code to test it out... I think A, B and E are correct ?? Try writing some snippets to prove me right or prove me wrong.



Result:
 
Greenhorn
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Jessica ,

Can we justify the above question posted by Peter Carter without knowing the contents for the wrapper objects. I mean as you have shown in ur code snippet
Integer i = new Integer(2); ---- how can we get the answers without the contents of the objects, as the above instruction shows 2.
 
Ranch Hand
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b is incorrect. Try the following code:



It outputs

a not == b
a equals b

They are two different wrapper objects which both wrap 2.
 
Greenhorn
Posts: 8
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Code from j2dk1.4.2

I think answer is A,E
 
Don't get me started about those stupid light bulbs.
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