Chapter 9, Problem 16PP

Program Plan Intro

Modified implementation of “Data” class

Program plan:

• In a file “Filter.java”, create a package,
  • Create an interface “Filter”,
    • Declare a method “accept()”.
• In a file “Measurer.java”, create a package,
  • Create an interface “Measurer”,
    • Declare a method “measure()”.
• In a file “BalanceFilter.java”,
  • Create a package.
  • Create a class “BalanceFilter”,
    • Define a method “accept()” to return the balance no less than $1000.
• In a file “BalanceMeasurer.java”,
  • Create a package.
  • Create a class “BalanceMeasurer”,
    • Define a method “measure()” to return the bank balance.
• In a file “BankAccount.java”,
  • Create a package.
  • Create a class “BankAccount”,
    • Declare the variable.
    • Define the constructor to create a bank account with “0” balance.
    • Define the parameterized constructor to update the balance with the specified amount.
    • Define a method “deposit()”  to update with the credited amount.
    • Define a method “withdraw()” to update the balance with withdrawal amount.
    • Define a method “getBalance()” to return the bank balance.
    • Define a method “addInterst()”to update the balance with interest.
• In a file “Data.java”, create a package and then a class “Data”,
  • Define a method “average()”,
    • Initialize the “sum”, and “num” variables to “0”.
    • Create “for” loop to iterate objects,
      • Update “sum” value.
      • Increment “num” value.
        • Check whether the value is positive,
        • • Return the value, which is calculated from dividing “sum” by “num”..
        • Otherwise,
        • • Return “0”.
• In a file “FilterDemo.java”, create a package and then a class “FilterDemo”,
  • Define the method “main()”,
    • Create an array of “BankAccount” objects.
    • Set the 0th array object value.
    • Set the first array object value.
    • Set the second array object value.
    • Set the third array object value.
    • Set the fourth array object value.
    • Create an object for “BalanceMeasurer” class.
    • Create an object for “BalanceFilter” class.
    • Print the value returned from the method “average()”.
    • Print the expected value.