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what is the output and why?  RSS feed

 
sonir shah
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class ArrayTest
{
public static void main(String[] args)
{
int ia[][] = { {1, 2}, null };
for (int i = 0; i < 2; i++)
for (int j = 0; j < 2; j++)
System.out.println(ia[i][j]);
}
}
 
Rashmi Tambe
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Hi,
U shuld have tried this code na du would have gor the answer... anyways...the o/p is:
1
2
Exception in thread "main" java.lang.NullPointerException
at ArrayTest.main(ArrayTest.java:8)
this is because ...
int ia[][] = { {1, 2}, null };
and when the loop tries to print ia[1][0], the exception is throws as the second reference in multidiamentional array ia is null.
Hope this helps.
Rashmi
 
sonir shah
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Thanx Rashmi
 
R K Singh
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1
Java Spring
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<pre>
class ArrayTest
{
public static void main(String[] args)
{
int ia[][] = { {1, 2}, null };// 1: compiles
int ib[] = {1, null}; // 2: DOES NOT compile
}
}
</pre>
Hi
why stmt 2: does not compile while 1: compiles
thanks in adv.
------------------
Regards
Ravish
 
anand raman
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hi ravish
int ib[] = {1, null}; // 2: DOES NOT compile
You are defining a single dimensional array of integer primitives. By doing this you are trying to assign a null value to a primitve int, which cant happen. Thus the compiler complains.
On the other hand.
int ia[][] = { {1, 2}, null };
is a multi dimensional array and expects multiple primitive int arrays. By doing this you are setting the second primitive int array to null..
Hope this helps
Anand
 
It is sorta covered in the JavaRanch Style Guide.
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