Assignment 1

Assignment 1

/**
 * James Kidd
 * Student ID: S3316990
 */

import java.io.PrintStream;
import java.util.Scanner;

public class Stage3
{
   // Tax brackets, and base rates
   static final double TAX_ONE_MAX = 10000;

   static final double TAX_TWO_MIN = 10000;
   static final double TAX_TWO_MAX = 40000;
   static final double TAX_TWO_BASE = 0.0;
   static final double TAX_TWO = 0.15;

   static final double TAX_THREE_MIN = 40000;
   static final double TAX_THREE_MAX = 80000;
   static final double TAX_THREE_BASE = 4500;
   static final double TAX_THREE = 0.30;

   static final double TAX_FOUR_MIN = 80000;
   static final double TAX_FOUR_MAX = 120000;
   static final double TAX_FOUR_BASE = 16500;
   static final double TAX_FOUR = 0.40;

   static final double TAX_FIVE_MIN = 120000;
   static final double TAX_FIVE_MAX = Double.MAX_VALUE;
   static final double TAX_FIVE_BASE = 32500;
   static final double TAX_FIVE = 0.45;

   static final double MEDICARE_LEVY = 0.015;

   // Formating strings for output
   private static final String FORMAT_SF = "%-25s $ %10.2f\n";
   private static final String FORMAT_SS = "%-25s %s\n";

   // Helpers to save typing, simplify code and keep under 80chars.
   private static Scanner _in;
   private static PrintStream _out = System.out;

   public static void main(String[] args)
   {
      // Initialize variables and inputs.
      _in = new Scanner(System.in);
      String financialYear, name, taxFileNumber;
      double income = 0.0, bankInterest = 0.0;
      double superContribution = 0.0, claimedDeductions = 0.0;
      double totalDeductions, totalIncome;

      // Read in all required inputs
      _out.println("*** Final Income Tax Calculator ***");
      _out.print("Enter Name:");
      name = _in.nextLine();

      _out.print("Enter Tax File Number (TFN):");
      taxFileNumber = _in.nextLine();

      _out.print("Enter financial year:");
      financialYear = _in.nextLine();

      // Input prompt loop for menu system
      while (true)
      {
         displayMenu();
         String menuChoice = _in.nextLine();
         if (menuChoice == null || menuChoice.length() == 0)
            continue;
         menuChoice = menuChoice.toUpperCase();
         if (menuChoice.charAt(0) == 'X')
            break;
         switch (menuChoice.charAt(0))
         {
            case 'A':
               _out.printf("Enter assesable income for period %s:",
                           financialYear);
               income += readDouble();
               break;
            case 'B':
               _out.print("Enter Bank interest accurued:");
               bankInterest += readDouble();
               break;
            case 'C':
               _out.printf("Enter pre-tax superannuation contribution for period %s:",
                           financialYear);
               superContribution += readDouble();
               break;
            case 'D':
               _out.printf("Enter claimable deduction(s) for period %s:",
                           financialYear);
               claimedDeductions += readDouble();
               break;
            case 'X':
               break;

            default:
               _out.println("Unexpected menu choice");
               break;
         }
      }
      // Calculate our total income, deductions and payable tax.
      totalDeductions = (claimedDeductions + superContribution);
      totalIncome = (income + bankInterest);
      double taxableIncome = totalIncome - totalDeductions;
      double payableTax = 0.0;

      if (taxableIncome <= TAX_ONE_MAX)
      {
      }
      else if (taxableIncome <= TAX_TWO_MAX)
      {
         payableTax = (taxableIncome - TAX_TWO_MIN) * TAX_TWO + TAX_TWO_BASE;
      }
      else if (taxableIncome <= TAX_THREE_MAX)
      {
         payableTax =
                  (taxableIncome - TAX_THREE_MIN) * TAX_THREE + TAX_THREE_BASE;
      }
      else if (taxableIncome <= TAX_FOUR_MAX)
      {
         payableTax = (taxableIncome - TAX_FOUR_MIN) * TAX_FOUR + TAX_FOUR_BASE;
      }
      else if (taxableIncome <= TAX_FIVE_MAX)
      {
         payableTax = (taxableIncome - TAX_FIVE_MIN) * TAX_FIVE + TAX_FIVE_BASE;
      }

      // Check for Medicare levy and calculate if needed. Prompt for Tax agents
      // name.
      boolean hasHealthcare;
      String taxAgentName;
      double payableMedicareLevy = 0.0;
      _out.print("Does the taxpayer currently have private health insurance? (Y/N):");
      hasHealthcare = readTextualBoolean();
      if (!hasHealthcare)
         payableMedicareLevy = taxableIncome * MEDICARE_LEVY;

      _out.print("Enter tax agent name:");
      taxAgentName = _in.nextLine();

      // Output the results.
      _out.printf("%35s", "*** Final Tax Statement ***\n\n");
      _out.printf(FORMAT_SS, "Name:", name);
      _out.printf(FORMAT_SS, "Tax File Number:", taxFileNumber);
      _out.println(String.format(FORMAT_SS, "Financial Year:", financialYear));

      _out.printf(FORMAT_SF, "Assesable Income:", totalIncome);
      _out.printf(FORMAT_SF, "Minus Tax Offsets:", -totalDeductions);
      _out.println(String.format(FORMAT_SF, "Taxable Income:", taxableIncome));

      _out.printf(FORMAT_SF, "Tax Payable:", payableTax);
      if (!hasHealthcare)
         _out.printf(FORMAT_SF, "Medicare levy:",
                     payableMedicareLevy);
      _out.printf("Tax Agent: %s\n", taxAgentName);
   }

   private static void displayMenu()
   {
      _out.println("--------------");
      _out.println("*** Taxation Data Entry System *** ");
      _out.println("A - Add assessable income");
      _out.println("B - Add interest accrued from bank account");
      _out.println("C - Add pre-tax superannuation contribution");
      _out.println("D - Add claimable deduction");
      _out.println("X - Exit and compile final taxation statement");
      _out.print("Enter your selection:");
   }

   /**
    * Helper Method to read in a double and handle removal of dollar signs.
    * 
    * @return Double value without leading $
    */
   private static double readDouble()
   {
      String result = _in.nextLine();
      double res = Double.parseDouble(result.replace("$", ""));
      return res;
   }

   /**
    * Helper Method to read Y/N as a boolean value.
    * 
    * @return true for Y/y else false.
    */
   private static boolean readTextualBoolean()
   {
      String res = _in.nextLine();
      boolean result = (res.charAt(0) == 'Y' || res.charAt(0) == 'y');
      return result;
   }
}