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InstanceOf Doubt.

 
Ranch Hand
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Source: http://www.go4java.20m.com/mock1.htm
Here the answer is null,false,false.But null IS-A Object, then why is the answer false?

1 class AA{}
2 class BB extends AA{}
3 class Q6
4 {
5 public static void main(String arg[])
6 {
7 AA a=null;
8 BB b=(BB)a;
9 System.out.println(b);
10 System.out.println(b instanceof BB);
11 System.out.println(b instanceof AA);
12 }
13 }
 
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null instanceof any type will always result in false. You can read the Java Language Specification for that...
 
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Originally posted by Abhi vijay:
But null IS-A Object...


No, null is not an object in Java. Where did you hear or read that null is an object?
 
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