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equals() for wrapper classes

 
Greenhorn
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I saw this in one of the mock tests.... I don't agree with the answer that was given for this question.
Q) Suppose 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.equals(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 given is B, C
I think the answer should be A and E.
A because equals should satisfy the reflexive property.
E because equals method return false if objects of different wrapper classes are compared.
C cant be true because it violates the symmetric property.
Am i right?

Thanks,
Neelima
 
Greenhorn
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Yes Neelima I agree with you....
It should go in the same way as u think
Other JavaRanchers Please confirm
 
Ranch Hand
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Hi,

A. b.equals(b) returns true.
B. b.equals(c) returns the same result as b == c.
C. b.equals(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.

A is Right
B is Wrong
C is Wrong
D is Wrong
E is Right
 
Ranch Hand
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Hi frnds

I have a doubt that only StringBuffer class doesnt override the equals method ??...is there anyother class??

thanks

sri
 
Sandeep Chhabra
Ranch Hand
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I think as far as SCJP Curriculum is concerned only StringBuffer class is an exception.
 
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