Java Tax Calculator problems

Question

I am trying to create a income tax calculator in java, and i got it to run, but it freezes up when i try to put in my marital status. can anybody tell me what I am going wrong? any help would be greatly appreciated. Code:

import java.util.Scanner;

public class TaxCalculator {
    public static void main(String[] args) {
        final double RATE1 = 0.20;
        final double RATE2 = 0.25;
        final double RATE3 = 0.10;
        final double RATE4 = 0.15;
        final double RATE5 = 0.30;
        final double RATE1_SINGLE_LIMIT = 0;
        final double RATE2_MARRIED_LIMIT = 0;
        final double RATE3_COHABITATING_LIMIT = 20000;
        final double RATE4_COHABITATING_LIMIT = 50000;
        double tax1 = 0;
        double tax2 = 0;
        double tax3 = 0;
        double tax4 = 0;
        double tax5 = 0;

        //Enter Income
        Scanner in = new Scanner(System.in);
        System.out.print("Please enter your income: ");
        double income = in.nextDouble();

        System.out.print("Please enter 's' for single, 'm' for married, or 'c' for cohabitating: ");
        String maritalStatus = in.next();

        //Calculate Taxes

        if (maritalStatus.equals("s"));
        //nested if

        if (income > RATE1_SINGLE_LIMIT) {
            tax1 = RATE1 * income;
        }

        if (maritalStatus.equals("m"));
        
        if (income > RATE2_MARRIED_LIMIT) {
            tax2 = RATE2 * income;
        }

        if (maritalStatus.equals("c"));
        
        if (income <= RATE3_COHABITATING_LIMIT) {
            tax3 = RATE3 * income;
        }   
        
        if (maritalStatus.equals("c"));
        
        if (income <= RATE4_COHABITATING_LIMIT) {
            tax4 = RATE4 * income;
        } else {
            tax5= RATE5 * income;
        }
    }
}

Answer 1

Put in.nextLine(); after double income = in.nextDouble(); and after String maritalStatus = in.next();. This is one of the solutions. The nextLine method will consume the new line (line feed) character, which is created in the input buffer by hitting Enter.

Answer 2

The nested if statements should look like this (note inverted comparison of String literal to the data input by user):

if ("s".equals(maritalStatus)) {
    if (income > RATE1_SINGLE_LIMIT) {
        tax1 = RATE1 * income;
    }
} else if ("m".equals(maritalStatus)) {
    if (income > RATE2_MARRIED_LIMIT) {
        tax2 = RATE2 * income;
    }
} else if ("c".equals(maritalStatus)) {
    if (income <= RATE3_COHABITATING_LIMIT) {
        tax3 = RATE3 * income;
    }   
    if (income <= RATE4_COHABITATING_LIMIT) {
        tax4 = RATE4 * income;
    } else {
        tax5= RATE5 * income;
    }
}

// add output line
System.out.println("marital status:" +  maritalStatus + "; income=" + income + " -> " + Arrays.asList(tax1, tax2, tax3, tax4, tax5));

Output:

Please enter your income: 3300
Please enter 's' for single, 'm' for married, or 'c' for cohabitating: m
marital status:m; income=3300.0 -> [0.0, 825.0, 0.0, 0.0, 0.0]

Answer 3

1. fix your if statements and remove redundant taxN variables.
2. Add in.nextLine() after each Scanner entry.

.

import java.util.Scanner;

public class TaxCalculator {
    static void calculate() {

        final double RATE1 = 0.20;
        final double RATE2 = 0.25;
        final double RATE3 = 0.10;
        final double RATE4 = 0.15;
        final double RATE5 = 0.30;
        final double RATE1_SINGLE_LIMIT = 0;
        final double RATE2_MARRIED_LIMIT = 0;
        final double RATE3_COHABITATING_LIMIT = 20000;
        final double RATE4_COHABITATING_LIMIT = 50000;
        double tax = 0;
        Scanner in = new Scanner(System.in);
        //Enter Income
        System.out.print("Please enter your income: ");
        double income = in.nextDouble();
        in.nextLine();

        System.out.print("Please enter 's' for single, 'm' for married, or 'c' for cohabitating: ");
        String maritalStatus = in.next();
        in.nextLine();

        //Calculate Taxes

        if (maritalStatus.equals("s") && income > RATE1_SINGLE_LIMIT) {
            tax = RATE1 * income;
        } else if (maritalStatus.equals("m") && income > RATE2_MARRIED_LIMIT) {
            tax = RATE2 * income;
        } else if (maritalStatus.equals("c") && income <= RATE3_COHABITATING_LIMIT) {
            tax = RATE3 * income;
        } else if (maritalStatus.equals("c") && income <= RATE4_COHABITATING_LIMIT) {
            tax = RATE4 * income;
        } else {
            tax = RATE5 * income;
        }

        System.out.print("Your tax is: " + tax);

    }

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String newResponse = "";
        do {
            calculate();
            System.out.println();
            System.out.println("Process another response?. Please enter 'y' for yes, or 'n' for no: ");
            newResponse = in.next();
            in.nextLine();
        } while (newResponse.equals("y"));

    }
}