Java with JOptionpane GUI and elseif value

Question

My java program has an equation that isn't recognizing a double value (double PropertyTax) from within brackets so that it can be used in an equation. Any suggestions? Thanks

import javax.swing.JOptionPane;
import java.util.Scanner;

public class CSC212{

public static void main(String[] args){

    Scanner in = new Scanner(System.in);

    String State = JOptionPane.showInputDialog("Enter the location ex: CA, AZ, WA, ect...");

                if(State == "AL")

        {
            double PropertyTax = 0.33;
        }

        else if(State == "AK")
        {
            double PropertyTax = 1.04;
        }

        else if(State == "AZ")
        {
            double PropertyTax = 0.72;
        }

        else if(State == "AR")
        {
            double PropertyTax = 0.52;
        }

        else if(State == "CA")
        {
            double PropertyTax = 0.74;
        }

        else if(State == "CO")
        {
            double PropertyTax = 0.6;
        }

        else if(State == "CT")
        {
            double PropertyTax = 1.63;
        }

        else if(State == "DE")
        {
            double PropertyTax = 0.43;
        }

        else if(State == "FL")
        {
            double PropertyTax = 0.97;
        }

        else if(State == "GA")
        {
            double PropertyTax = 0.83;
        }

        else if(State == "HI")
        {
            double PropertyTax = 0.26;
        }

        else if(State == "ID")
        {
            double PropertyTax = 0.69;
        }

        else if(State == "IL")
        {
            double PropertyTax = 1.73;
        }

        else if(State == "IN")
        {
            double PropertyTax = 0.85;
        }

        else if(State == "IA")
        {
            double PropertyTax = 1.29;
        }

        else if(State == "KS")
        {
            double PropertyTax = 1.01;
        }

        else if(State == "KY")
        {
            double PropertyTax = 0.72;
        }

        else if(State == "LA")
        {
            double PropertyTax = 0.18;
        }

        else if(State == "ME")
        {
            double PropertyTax = 1.09;
        }

        else if(State == "MD")
        {
            double PropertyTax = 0.87;
        }

        else if(State == "MA")
        {
            double PropertyTax = 1.04;
        }

        else if(State == "MI")
        {
            double PropertyTax = 1.05;
        }

        else if(State == "MN")
        {
            double PropertyTax = 1.05;
        }

        else if(State == "MS")
        {
            double PropertyTax = 0.52;
        }

        else if(State == "MO")
        {
            double PropertyTax = 0.91;
        }

        else if(State == "MT")
        {
            double PropertyTax = 0.83;
        }

        else if(State == "NE")
        {
            double PropertyTax = 1.76;
        }

        else if(State == "NV")
        {
            double PropertyTax = 0.84;
        }

        else if(State == "NH")
        {
            double PropertyTax = 1.86;
        }

        else if(State == "NJ")
        {
            double PropertyTax = 1.89;
        }

        else if(State == "NM")
        {
            double PropertyTax = 0.55;
        }

        else if(State == "NY")
        {
            double PropertyTax = 1.23;
        }

        else if(State == "NC")
        {
            double PropertyTax = 0.78;
        }

        else if(State == "ND")
        {
            double PropertyTax = 1.42;
        }

        else if(State == "OH")
        {
            double PropertyTax = 1.36;
        }

        else if(State == "OK")
        {
            double PropertyTax = 0.74;
        }

        else if(State == "OR")
        {
            double PropertyTax = 0.87;
        }

        else if(State == "PA")
        {
            double PropertyTax = 1.35;
        }

        else if(State == "RI")
        {
            double PropertyTax = 1.35;
        }

        else if(State == "SC")
        {
            double PropertyTax = 0.5;
        }

        else if(State == "D.C.")
        {
            double PropertyTax = 0.46;
        }

        else if(State == "SD")
        {
            double PropertyTax = 1.28;
        }

        else if(State == "TN")
        {
            double PropertyTax = 0.86;
        }

        else if(State == "TX")
        {
            double PropertyTax = 1.18;
        }

        else if(State == "UT")
        {
            double PropertyTax = 0.6;
        }

        else if(State == "VT")
        {
            double PropertyTax = 1.59;
        }

        else if(State == "WA")
        {
            double PropertyTax = 0.92;
        }

        else if(State == "WV")
        {
            double PropertyTax = 0.49;
        }

        else if(State == "WI")
        {
            double PropertyTax = 1.76;
        }

        else if(State == "WY")
        {
            double PropertyTax = 0.58;
        }

    String houseValue = JOptionPane.showInputDialog("Enter the value of the home");
        double hValue = Integer.parseInt(houseValue);

    double product = PropertyTax * hValue;


   JOptionPane.showMessageDialog(null, "The property tax is " +product);  

            }

}

Also, see [How do I compare strings in Java?](https://stackoverflow.com/questions/513832/how-do-i-compare-strings-in-java) — khelwood, Apr 05 '20 at 02:09
`double propertyTax =0; if(State.equals( "AL")) propertyTax = 0.33;` — c0der, Apr 05 '20 at 06:55

score 0 · Answer 1 · answered Apr 05 '20 at 08:06

You could do this another way and eliminate all the if/else statements. Show a List of states within the Input Box from where the User can select the desired state The index of the selection is in relation to a parallel array that contains all the Tex Rates for each state. There are several ways to make this easier.

// Component for JOptionPane to ensure it is always displayed on top
JFrame iFrame = new JFrame();
iFrame.setAlwaysOnTop(true);
iFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
iFrame.setLocationRelativeTo(null);

double propertyTax = 0.0d;

// Parallel Arrays
// List values t display in Input-Box
String[] states = {"Alabama", "Alaska", "Arizona", "Arkansas", "California",
    "Colorado", "Connecticut", "Delaware", "Florida", "Georgia",
    "Hawaii", "Idaho", "Illinois", "Indiana", "Iowa", "Kansas",
    "Kentucky", "Louisiana", "Maine", "Maryland", "Massachusetts",
    "Michigan", "Minnesota", "Mississippi", "Missouri", "Montana",
    "Nebraska", "Nevada", "New Hampshire", "New Jersey", "New Mexico",
    "New York", "North Carolina", "North Dakota", "Ohio", "Oklahoma",
    "Oregon", "Pennsylvania", "Rhode Island", "South Carolina",
    "South Dakota", "Tennessee", "Texas", "Utah", "Vermont", "Virginia",
    "Washington", "West Virginia", "Wisconsin", "Wyoming"};

// Tax rates related to the above States
double[] taxes = {0.33d, 1.04d, 0.72d, 0.52d, 0.74d, 0.6d, 1.63d, 0.43d,
    0.97d, 0.83d, 0.26d, 0.69d, 1.73d, 0.85d, 1.29d, 1.01d,
    0.72d, 0.18, 1.04d, 1.09d, 0.87d, 1.05d, 1.05d, 0.52d,
    0.91d, 0.83d, 1.76d, 0.84d, 1.86d, 1.89d, 0.55d, 1.23d,
    0.78d, 1.42d, 1.36d, 0.74d, 0.87d, 1.35d, 1.35d, 0.5d,
    0.46d, 1.28d, 0.86d, 1.18d, 0.6d, 1.59d, 0.92d, 0.49d,
    1.76d, 0.58d};

// Show Input-Box dialog...
String selectedState = (String) JOptionPane.showInputDialog(iFrame, "Select a State:",
        "State Selection", JOptionPane.QUESTION_MESSAGE, null, states, "");
iFrame.dispose();

if (selectedState != null && !selectedState.equals("")) {
    // Get the index value of the selected State so as
    // to get the tax rate related to that state.
    for (int i = 0; i < states.length; i++) {
        if (selectedState.equals(states[i])) {
            propertyTax = taxes[i];
            break;
        }
    }

    // Get house value from User...
    String houseValue = JOptionPane.showInputDialog(iFrame, "Enter the value of the home", "Home Value",
            JOptionPane.QUESTION_MESSAGE);
    if (houseValue == null || houseValue.equals("")) {
        houseValue = "0.0";
    }
    iFrame.dispose();
    double hValue = Double.parseDouble(houseValue);

    // Calculate the property tax
    double product = hValue * (propertyTax / 100.0d);

    // Display results... 
    JOptionPane.showMessageDialog(iFrame, "The property tax is " + product);
    iFrame.dispose();
}

Not necessarily shorter but it does eliminate the possibility of typos by the User.

Java with JOptionpane GUI and elseif value

1 Answers1