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Inheritance-1

 
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Code:
---------------------------------------------------
class AA {
}

class BB extends AA {
}

class Class24 {
public static void main(String arg[]) {
AA a = null;
BB b = (BB) a;
System.out.println(b instanceof AA);
System.out.println(b instanceof BB);
}
}
--------------------------------------------------------------

Output: false,false

Query: Why the output is false for the above code. Please give explanation for that.
 
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Regarding the specs for the instanceof operaor : if the left operand is null, result is always false.
 
Consider Paul's rocket mass heater.
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