2014 US Federal Tax Calculator

TaxCalculator.java

public class TaxCalculator implements TaxLookup
{


    public static double getTax(int income, int status)
    {
        double tax = 0;
        for (int i = 0; i < 7; i++)
        {
            if (income > lookup[status][i][1])
            {
                    tax = lookup[status][i][0] + (income - lookup[status][i][1]) * lookup[status][i][2];
            }
        }
        return tax;
    }

    public static int getBracket(int income, int status)
    {
        int bracket = 0;
        for (int i = 0; i < 7; i++)
        {
            if (income > lookup[status][i][1])
            {
                    bracket = (int)(lookup[status][i][2]*100);
            }
        }
        return bracket;

    }
}

TaxCalculatorGUI.java

import java.awt.event.KeyEvent;
import javax.swing.JOptionPane;


public class TaxCalculatorGUI extends javax.swing.JFrame {

    public TaxCalculatorGUI() {
        initComponents();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">//GEN-BEGIN:initComponents
    private void initComponents() {

        jLabel1 = new javax.swing.JLabel();
        cmbFilingStatus = new javax.swing.JComboBox();
        jLabel2 = new javax.swing.JLabel();
        txtIncome = new javax.swing.JTextField();
        btnCalculate = new javax.swing.JButton();
        jLabel3 = new javax.swing.JLabel();
        lblTax = new javax.swing.JLabel();
        jLabel4 = new javax.swing.JLabel();
        lblBracket = new javax.swing.JLabel();
        jLabel5 = new javax.swing.JLabel();
        lblPercent = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("Tax Calculator Federal 2015");

        jLabel1.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        jLabel1.setText("Enter Filing Status:");

        cmbFilingStatus.setFont(new java.awt.Font("Tahoma", 0, 12)); // NOI18N
        cmbFilingStatus.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "Single", "Married - Filing Jointly", "Married - Filing Seperately", "Head of Household" }));
        cmbFilingStatus.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                cmbFilingStatusActionPerformed(evt);
            }
        });

        jLabel2.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        jLabel2.setText("Enter Taxable Income (rounded up to nearest dollar):");

        txtIncome.setFont(new java.awt.Font("Tahoma", 0, 12)); // NOI18N
        txtIncome.addKeyListener(new java.awt.event.KeyAdapter() {
            public void keyPressed(java.awt.event.KeyEvent evt) {
                txtIncomeKeyPressed(evt);
            }
        });

        btnCalculate.setText("Calculate");
        btnCalculate.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnCalculateActionPerformed(evt);
            }
        });

        jLabel3.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        jLabel3.setText("Your Income Tax is:");

        lblTax.setFont(new java.awt.Font("Tahoma", 1, 14)); // NOI18N
        lblTax.setText("$");

        jLabel4.setText("Your Income Tax Bracket:");

        lblBracket.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        lblBracket.setText("%");

        jLabel5.setText("Your tax as % of income:");

        lblPercent.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
        lblPercent.setText("%");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addGap(63, 63, 63)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addGroup(layout.createSequentialGroup()
                                .addComponent(jLabel1)
                                .addGap(18, 18, 18)
                                .addComponent(cmbFilingStatus, javax.swing.GroupLayout.PREFERRED_SIZE, 247, javax.swing.GroupLayout.PREFERRED_SIZE))
                            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                                .addComponent(jLabel2)
                                .addComponent(btnCalculate)
                                .addComponent(txtIncome, javax.swing.GroupLayout.PREFERRED_SIZE, 191, javax.swing.GroupLayout.PREFERRED_SIZE))))
                    .addGroup(layout.createSequentialGroup()
                        .addGap(69, 69, 69)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                            .addComponent(jLabel4)
                            .addComponent(jLabel3)
                            .addComponent(jLabel5))
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(lblTax, javax.swing.GroupLayout.PREFERRED_SIZE, 174, javax.swing.GroupLayout.PREFERRED_SIZE)
                            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING, false)
                                .addComponent(lblBracket, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.DEFAULT_SIZE, 70, Short.MAX_VALUE)
                                .addComponent(lblPercent, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)))))
                .addContainerGap(55, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(63, 63, 63)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel1)
                    .addComponent(cmbFilingStatus, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGap(43, 43, 43)
                .addComponent(jLabel2)
                .addGap(18, 18, 18)
                .addComponent(txtIncome, javax.swing.GroupLayout.PREFERRED_SIZE, 32, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(18, 18, 18)
                .addComponent(btnCalculate)
                .addGap(18, 18, 18)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(lblTax, javax.swing.GroupLayout.PREFERRED_SIZE, 40, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(jLabel3))
                .addGap(18, 18, 18)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel4)
                    .addComponent(lblBracket, javax.swing.GroupLayout.PREFERRED_SIZE, 23, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGap(18, 18, 18)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jLabel5)
                    .addComponent(lblPercent, javax.swing.GroupLayout.PREFERRED_SIZE, 23, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addContainerGap(16, Short.MAX_VALUE))
        );

        pack();
        setLocationRelativeTo(null);
    }// </editor-fold>//GEN-END:initComponents

    private void btnCalculateActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnCalculateActionPerformed
        try
        {
            int income = Integer.parseInt(txtIncome.getText());
            double tax = (TaxCalculator.getTax(income, cmbFilingStatus.getSelectedIndex()) * 100) /100;
            String formattedTax = String.format("$ %,.2f", tax);
            lblTax.setText(formattedTax);
            lblBracket.setText(TaxCalculator.getBracket(income, cmbFilingStatus.getSelectedIndex()) + "%");
            double percent = (tax / income) * 100;
            lblPercent.setText(String.format("%.2f%%", percent));
        }
        catch (NumberFormatException nfe)
        {
            JOptionPane.showMessageDialog(rootPane, "Must be a valid number", "Error", JOptionPane.ERROR_MESSAGE);
            txtIncome.requestFocusInWindow();
            txtIncome.setText("");
        }
    }//GEN-LAST:event_btnCalculateActionPerformed

    private void cmbFilingStatusActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_cmbFilingStatusActionPerformed
        if (!txtIncome.getText().isEmpty())
        {
            btnCalculate.doClick();
        }
    }//GEN-LAST:event_cmbFilingStatusActionPerformed

    private void txtIncomeKeyPressed(java.awt.event.KeyEvent evt) {//GEN-FIRST:event_txtIncomeKeyPressed
        int key = evt.getKeyCode();
        if (key==KeyEvent.VK_ENTER)
        {
            btnCalculate.doClick();
        }
    }//GEN-LAST:event_txtIncomeKeyPressed

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(TaxCalculatorGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(TaxCalculatorGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(TaxCalculatorGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(TaxCalculatorGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new TaxCalculatorGUI().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify//GEN-BEGIN:variables
    private javax.swing.JButton btnCalculate;
    private javax.swing.JComboBox cmbFilingStatus;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JLabel jLabel3;
    private javax.swing.JLabel jLabel4;
    private javax.swing.JLabel jLabel5;
    private javax.swing.JLabel lblBracket;
    private javax.swing.JLabel lblPercent;
    private javax.swing.JLabel lblTax;
    private javax.swing.JTextField txtIncome;
    // End of variables declaration//GEN-END:variables
}

TaxLookup.java

public interface TaxLookup {
   	double[][][] lookup = {
                                {
                                        // status 0
                                        { 0 , 0, 0.10},
                                        { 907.50, 9075, 0.15},
                                        { 5081.25, 36900, 0.25},
                                        { 18193.75, 89350, 0.28},
                                        { 45353.75, 186350, 0.33},
                                        { 117541.25, 405100, 0.35 },
                                        { 118118.75, 406750, 0.396 }
                                },
                                {
                                        // status 1
                                        { 0, 0, 0.10 },
                                        { 1815, 18150, 0.15 },
                                        { 10162.50, 73800, 0.25 },
                                        { 28925, 148850, 0.28 },
                                        { 50765, 226850, 0.33 },
                                        { 109587.5, 405100, 0.35 },
                                        { 127962.5, 457600, 0.396 }
                                },
                                {
                                        // status 2
                                        { 0 , 0, 0.10 },
                                        { 907.50, 9075, 0.15 },
                                        { 5081.25, 36900, 0.25 },
                                        { 14462.5, 74425, 0.28 },
                                        { 25382.5, 113425, 0.33 },
                                        { 54793.75, 202550, 0.35 },
                                        { 63981.25, 228800, 0.396 }
                                },
                                {
                                        // status 3
                                        { 0, 0, 0.10 },
                                        { 1295, 12950, 0.15 },
                                        { 6762.5, 49400, 0.25 },
                                        { 26300, 127550, 0.28 },
                                        { 48434, 206600 , 0.33 },
                                        { 113939, 405100, 0.35 },
                                        { 123424, 432200, 0.396 }
                                }
                            };


}