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Jxam Question

 
Greenhorn
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Given the following definition:
String s = null;
Which code fragment will cause an exception of type NullPointerException to be thrown.
A. if ((s != null) & (s.length()>0))
B. if ((s != null) && (s.length()>0))
C. if ((s != null) | (s.length()>0))
D. if ((s != null) | | (s.length()>0))
The answer is given as all the options. My understanding was that the correct answers are only A, C & D. Since the second part of option 'B' will not get executed. Can you please clarify this?
THIRU
 
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I have done the same answer as you,
i also don't understand the answer supplied by Jxam.
B is correct, because && is short-circult operator.
 
Ranch Hand
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Hi Thiru,
Your understanding is absolutely correct. The correct answers are A, C and D as B is wrong becoz its short circuit operation. I tested the code, why don't you test it yourself
Jyotsna

Originally posted by Thiru Narayanan:
Given the following definition:
String s = null;
Which code fragment will cause an exception of type NullPointerException to be thrown.
A. if ((s != null) & (s.length()>0))
B. if ((s != null) && (s.length()>0))
C. if ((s != null) | (s.length()>0))
D. if ((s != null) | | (s.length()>0))
The answer is given as all the options. My understanding was that the correct answers are only A, C & D. Since the second part of option 'B' will not get executed. Can you please clarify this?
THIRU


 
Thiru Narayanan
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Thank you Jyotsna & Andrew,
I do not think there is any need to check it, as the short circuit '&&' will not execute the second part if the first part returns a 'false'
THIRU
 
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