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IS-A question from examlab mock test (Diagnostic Exam)

 
Ranch Hand
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An interface "is-a" java.lang.Object



Answer-I is correct, because any object, which has an interface-reference, can be implicitly casted to a java.lang.Object reference, without doing any explicit cast.


Is this statement right?
i didn`t get it. I think that interface is not class and so not is-a Object.
 
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In the most general term: all objects in Java inherit from java.lang.Object, so yes any "object" that has an interface-reference can be cast to java.lang.Object

The child class is always guaranteed to have all references needed to be referenced by the parent class.
 
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