Assume the availability of an existing class, ICalculator, that models an integer arithmetic calculator and contains:
an instance variable currentValue that stores the current int value of the calculator a getter method for the above instance variable 
methods add, sub, mul, and div

Each method in ICalculator receives an int argument and applies its operation to currentValue and returns the new value of currentValue. So, if currentValue has the value 8 and sub(6) is invoked then currentValue ends up with the value 2, and 2 is returned. 

So, you are to prepare the definition of a subclass, ICalculator3, based on ICalculator. The class ICalculator3 overrides the div method of ICalculator. It checks its argument and if the argument is zero, it prints to standard output the message "ZERO DIVIDE ATTEMPT" and simply returns the value of currentValue. Otherwise, if the argument is NOT zero, the method invokes the base class method div (from ICalculator) and returns the value that it receives from that call.