The “instanceof” operator: The “instanceof” operator tests whether an object belongs to a particular type. For example, //use of instance of operator obj instanceof Question The above statement returns “true” if the type of “obj” is convertible to “Question”. This happens if “obj” refers to an actual class “Question” or to a subclass such as “ChoiceQuestion”. Class “Object”: The “Object” is the root class of library of java. By default, the class “Object” is the base class of all other java classes. Every class is subclass of class “Object”.

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Chapter 9.5, Problem 25SC

Program Plan Intro

The “instanceof” operator:

The “instanceof” operator tests whether an object belongs to a particular type.

For example,
//use of instance of operator

obj instanceof Question

The above statement returns “true” if the type of “obj” is convertible to “Question”.

This happens if “obj” refers to an actual class “Question” or to a subclass such as “ChoiceQuestion”.

Class “Object”:

The “Object” is the root class of library of java.

By default, the class “Object” is the base class of all other java classes.

Every class is subclass of class “Object”.

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