Quession on if(){} and so on

[Hades Pan]

class sreejith
{
String s;
public static void main(String args[])
{
sreejith ks=new sreejith();
int j,i;
i=ks.hai();
j=ks.hello();
System.out.println(i+" "+j);
}
int hai()
{
if (s==null)| | (s.length()==0))
return 10;
else return 0;
}
int hello()
{
if (s==null)| (s.length()==20))
return 10;
else return 0;
}
}
what will be printed out?
A. 10 10
B. 10 null
C. 0 0
D. Compilation Error
E. An Exception in hai
F. An Exception in hello
Ans is "F"
isn't A I have a doubt on it

[ruthie]

when s is null. the use of s.length() will throw an nullpointerexception

[Marilyn de Queiroz]

ruthie,
Please read http://www.javaranch.com/name.jsp and re-register. We would like you to continue to post here at JavaRanch.

[Hades Pan]

Originally posted by ruthie:
when s is null. the use of s.length() will throw an nullpointerexception

But s is null in if (s==null)| | (s.length()==0))
return 10;
else return 0;
}will throw an nullpointerexception too???

[vishal avad]

hi hardes
in ur question in first case i.e. first if condition
short circuit operator | | is used.
meaning of is that if first condition is true i.e. s==null which is true then the resultant condition is going to be true only
irrespective of second conditions result so check for s.lenght() is no going to execute but in case of next if it is executed
due to use of binary | operator
so it throws nullpointerexception
rgds
vishal