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Problem -- Virtual Method Invocation

Niyas Ahmed Sheikh
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Joined: Jun 15, 2005
Posts: 129

Below is the sample coding I had written to test virtual method invocation:

While compiling, it didn't display any error and even when I run the program it displays the output, but the last line it's give error message:

Steve Simon Joseph Fernandez
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Joined: Jul 17, 2005
Posts: 35

In the last block given below

you're checking whether p1 is an instance of Child, but inside the condition, you're trying to cast p to a Child. Assigning a superclass object to a subclass reference is illegal. Although the compiler allows it, the JVM will report a ClassCastException.

I agree. Here's the link:
subject: Problem -- Virtual Method Invocation
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