ooConcepts/calcWithInstanceVariables

[judiMc]

[judiMc]

This practice problem builds on the one presented as practice problem for Instance Methods. If you have not completed that activity, please do so. The calculator can be made more useful by adding variables to hold values between method invocations. In this way the calculator's methods can operate on the value stored in an instance variable and multiple calculators could have separate values. Modify the calculator class so that it has a double as an instance variable. It should store the results of every calculation in that variable and provide a mechanism for retrieving the value (an accessor method). This instance variable should not have a mutator method. Adjust the instance methods so that they no longer take two parameters. Instead they simply perform the calculation with the value currently held by the calculator. Test your revised calculator thoroughly in the Runner class.