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Boolean values

 
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Source :Sreenivasa Kumar Majji's Questions javaranch(FAQ)

some body please help me with following question:

[B]Q what is the output




answer is D) False

I thought it would be true due to auto boxing.I ran the code and it is coming FALSE only.I know i am missing something somewhere.

When I run the following code:
[/B]
output is True

In code below there is no output
[B]

Doesn't auto boxing applies to boolean.

Regards
 
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Eclipse IDE Java Linux
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Hi,
When you are comparing two object references using == operator, it checks whether they are pointing to same object or not.



In above two cases you are creating two objects using new operator so it always gives always false as output,

In below case


you are comparing object with primitive so un boxing happens here and object will be converted to primitive that is why result of comparison is true
 
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Check also page 236 in the SCJP 1.5 study guide.
 
Sunny Mattas
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thank you for your efforts

I got the point.

Regards
 
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Hi Sunny,

take a look at this example:



See that Integers between -128 and 127 initialzed with literal will always have the same reference, because java has a pool for it.

It works for Characters, Booleans, Longs, Integers, Shorts ands Bytes.
If i forgot any other, please, someone say please.
[ July 18, 2008: Message edited by: Raphael Rabadan ]
 
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See that Integers between -128 and 127 initialzed with literal will always have the same reference, because java has a pool for it.

It works for Characters, Booleans, Longs, Integers, Shorts ands Bytes.
If i forgot any other, please, someone say please.




and ofcourse, the famous one - "Strings" ..
[ July 18, 2008: Message edited by: Sagar Rohankar ]
 
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hi,
Raphael Rabadan

Can you tell me why it is printing false for Integer i3 == Integer i4.
for i1==i2 it is printing true.can you clarify it.

regards
darshan
 
darshan karle
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sorry Raphael Rabadan

i didn't see the message you mentioned after the code.i am cleared

thanks
 
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