(Financial: the Tax class) Programming Exercise 8.12 writes a program for computing taxes using arrays. Design a class named Tax to contain the following instance data fields:

/*********************************************************************************
* (Financial: the Tax class) Programming Exercise 8.12 writes a program for      *
* computing taxes using arrays. Design a class named Tax to contain the          *
* following instance data fields:                                                *
*                                                                                *
* ■ int filingStatus: One of the four tax-filing statuses: 0—single filer, 1—    *
* 	 married filing jointly or qualifying widow(er), 2—married filing separately, *
* 	 and 3—head of household. Use the public static constants SINGLE_FILER        *  
* 	 (0), MARRIED_JOINTLY_OR_QUALIFYING_WIDOW(ER) (1), MARRIED_                   *
* 	 SEPARATELY (2), HEAD_OF_HOUSEHOLD (3) to represent the statuses.             *
* ■ int[][] brackets: Stores the tax brackets for each filing status.            *
* ■ double[] rates: Stores the tax rates for each bracket.                       *
* ■ double taxableIncome: Stores the taxable income.                             *
*                                                                                *
* Provide the getter and setter methods for each data field and the getTax()     *
* method that returns the tax. Also provide a no-arg constructor and the         *
* constructor Tax(filingStatus, brackets, rates, taxableIncome).                 *
*                                                                                *
* Draw the UML diagram for the class and then implement the class. Write a test  *
* program that uses the Tax class to print the 2001 and 2009 tax tables for      *
* taxable income from $50,000 to $60,000 with intervals of $1,000 for all four   *
* statuses. The tax rates for the year 2009 were given in Table 3.2. The tax     *
* rates for 2001 are shown in Table 10.1.                                        *
*********************************************************************************/
public class Exercise_10_08 {
	/** Main method */
	public static void main(String[] args) {
		// Create two tax objects
		Tax tax2001 = new Tax();
		Tax tax2009 = new Tax(); // Current Year

		// Tax rates for 2001
		double[] rates2001 = {15, 27.5, 30.5, 35.5, 39.1};
		tax2001.setRates(rates2001);

		// The 2001 brackets for each rate for all the filing statuses
		int[][] brackets2001 = {
			{27050, 65550, 136750, 297350},  // Single filer
			{45200, 109250, 166500, 297350}, // Married jointly
														// -or qualifying widow(er)
			{22600, 54625, 83250, 148675},  	// Married separately
			{36250, 93650, 151650, 297350} 	// Head of household
		};
		tax2001.setBrackets(brackets2001);

		// Print tax tables for 2001 and 2009
		final double FROM = 50000;		// Start table taxable income range at $50,000
		final double TO = 60000;		// End table taxable income range at $60,000
		final double INTERVAL = 1000;	// Increase each row by $1000

		System.out.println(
			"\n2001 tax tables for taxable income from $50,000 to $60,000");
		print(tax2001, FROM, TO, INTERVAL);

		System.out.println(
			"\n2009 tax tables for taxable income from $50,000 to $60,000");
		print(tax2009, FROM, TO, INTERVAL);
		
	}

	/** Display taxable for  taxable income with specified range and interval */
	public static void print(Tax tax, double from, double to, double interval) {
		// Print header
		System.out.println(
			"---------------------------------------------------------------------\n" +
			"Taxable       Single      Married Joint       Married        Head of\n" +
			"Income                    or Qualifying       Separate       a House\n" +
			"                          Widow(er)\n" +
			"---------------------------------------------------------------------");
		// Print Data
		for (double taxableIncome = from; 
			  taxableIncome <= to; taxableIncome += interval) {
			tax.setTaxableIncome(taxableIncome);
			System.out.printf("%-13.0f", taxableIncome);
			tax.setFilingStatus(tax.SINGLE_FILER);
			System.out.printf("%8.2f", tax.getTax());
			tax.setFilingStatus(tax.MARRIED_JOINTLY_OR_QUALIFYING_WIDOWER);
			System.out.printf("%15.2f", tax.getTax());
			tax.setFilingStatus(tax.MARRIED_SEPARATELY);
			System.out.printf("%18.2f", tax.getTax());
			tax.setFilingStatus(tax.HEAD_OF_HOUSEHOLD);
			System.out.printf("%15.2f\n", tax.getTax());
		}
	}
}

Tax.java 

/************************************************
*                   Tax                         *
*-----------------------------------------------*
* -filingStatus: int                            *
* +SINGLE_FILER: int                            *
* ------------------                            *
* +MARRIED_JOINTLY_OR_QUALIFYING_WIDOW(ER): int *
* --------------------------------------------- *
* +MARRIED_SEPARATELY: int                      *
* ------------------------                      *
* +HEAD_OF_HOUSEHOLD: int                       *
* -----------------------                       *
* -brackets: int[][]                            *
* -rates: double[]                              *
* -taxableIncome: double                        *
* +Tax()                                        *
* +Tax(filingStatus: int, brackets: int[][],    * 
*      rates: double[], taxableIncome: double)  * 
* +getFilingStatus(): int                       *
* +setFilingStatus(status: int)                 *
* +getBrackets(): int[][]                       *
* +setBrackets(brackets: int[][])               *
* +getRates(): int[]                            *
* +setRates(rates: int[])                       *
* +getTaxableIncome(): double                   *
* +setTaxableIncome(taxableIncome: double)      *
* +getTax(): double                             *
************************************************/

// Implement Tax class
public class Tax {
	// Data fields
	private int filingStatus;
	public static final int SINGLE_FILER = 0;
	public static final int MARRIED_JOINTLY_OR_QUALIFYING_WIDOWER = 1;
	public static final int MARRIED_SEPARATELY = 2;
	public static final int HEAD_OF_HOUSEHOLD = 3;
	private int[][] brackets;
	private double[] rates;
	private double taxableIncome;

	// Construct a tax object with default 
	// filingStatus, rates, brackets and taxableIncome
	Tax() {
		// Defalut filing status
		filingStatus = SINGLE_FILER;

		// Defalut tax rates
		double[] currentYearRates = {10, 15, 25, 28, 33, 35};;
		setRates(currentYearRates);

		// Default brackets for each rate for all the filing statuses
		int[][] currentYearBrackets = {
			{8350, 33950, 82250, 171550, 372950},  // Single filer
			{16700, 67900, 137050, 20885, 372950}, // Married jointly
																// -or qualifying widow(er)
			{8350, 33950, 68525, 104425, 186475},  // Married separately
			{11950, 45500, 117450, 190200, 372950} // Head of household
		};
		setBrackets(currentYearBrackets);

		// Default taxable income
		taxableIncome = 0;

	}

	// Construct a tax object with specified
	// filingStatus, rates, brackets and taxableIncome
	Tax(int filingStatus, int[][] brackets, double[] rates, double taxableIncome) {
		setFilingStatus(filingStatus);
		setBrackets(brackets);
		setRates(rates);
		setTaxableIncome(taxableIncome);
	}

	/** Set a new filingStatus */
	public void setFilingStatus(int filingStatus) {
		this.filingStatus = filingStatus;
	}

	/** Return filingStatus */
	public int getFilingStatus() {
		return filingStatus;
	}

	/** set new brackets */
	public void setBrackets(int[][] brackets) {
		this.brackets = new int[brackets.length][brackets[0].length];
		for (int i = 0; i < brackets.length; i++) {
			for (int j = 0; j < brackets[i].length; j++)
				this.brackets[i][j] = brackets[i][j];
		}
	}

	/** Return brackets */
	public int[][] getBrackets() {
		return brackets;
	}

	/** Set new rates */
	public void setRates(double[] rates) {
		this.rates = new double[rates.length];
		for (int i = 0; i < rates.length; i++)
			this.rates[i] = rates[i] / 100;
	}

	/** Return rates */
	public double[] getRates() {
		return rates;
	}

	/** Set new taxableIncome */
	public void setTaxableIncome(double taxableIncome) {
		this.taxableIncome = taxableIncome;
	}

	/** Return Tax */
	public double getTax() {
		double tax = 0, incomeTaxed = 0;
		double income = taxableIncome; 
		if (rates.length >= 2) {
			for (int i = rates.length - 2; i >= 0; i--) {
				if (income > brackets[filingStatus][i]) {
 					tax += (incomeTaxed = income - brackets[filingStatus][i]) 
 								* rates[i + 1];
					income -= incomeTaxed;
 				}
			} 
		}
		return tax += brackets[filingStatus][0] * rates[0];
	}
}