Calculator.java

package Calculator;

/**
 *
 * @author Teahliana
 */
public class Calculator extends javax.swing.JFrame {

    boolean pressedAdd = false;
    boolean pressedSub = false;
    boolean pressedMul = false;
    boolean pressedDiv = false;
    int previousvalue = 0;
    boolean pressedSymbol = false;

    /**
     * Creates new form Calculator
     */
    public Calculator() {
        initComponents();
    }

    private void initComponents() {

        jPanel1 = new javax.swing.JPanel();
        txtDisplay = new javax.swing.JTextField();
        jPanel2 = new javax.swing.JPanel();
        btnOne = new javax.swing.JButton();
        btnTwo = new javax.swing.JButton();
        btnThree = new javax.swing.JButton();
        btnPlus = new javax.swing.JButton();
        btnFour = new javax.swing.JButton();
        btnFive = new javax.swing.JButton();
        btnSix = new javax.swing.JButton();
        btnSubstraction = new javax.swing.JButton();
        btnSeven = new javax.swing.JButton();
        btnEight = new javax.swing.JButton();
        btnNine = new javax.swing.JButton();
        btnMultiply = new javax.swing.JButton();
        btnDot = new javax.swing.JButton();
        BtnZero = new javax.swing.JButton();
        btnEqual = new javax.swing.JButton();
        btnDiv = new javax.swing.JButton();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jPanel1.setBackground(new java.awt.Color(255, 255, 255));

        txtDisplay.setEditable(false);
        txtDisplay.setFont(new java.awt.Font("Tahoma", 1, 36)); // NOI18N
        txtDisplay.setHorizontalAlignment(javax.swing.JTextField.RIGHT);
        txtDisplay.setText("0");

        javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(
                jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addGroup(jPanel1Layout.createSequentialGroup()
                                .addContainerGap()
                                .addComponent(txtDisplay, javax.swing.GroupLayout.PREFERRED_SIZE, 296,
                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)));
        jPanel1Layout.setVerticalGroup(
                jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addGroup(jPanel1Layout.createSequentialGroup()
                                .addContainerGap()
                                .addComponent(txtDisplay, javax.swing.GroupLayout.PREFERRED_SIZE, 50,
                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)));

        jPanel2.setBackground(new java.awt.Color(204, 204, 255));

        btnOne.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnOne.setText("1");
        btnOne.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnOneActionPerformed(evt);
            }
        });

        btnTwo.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnTwo.setText("2");
        btnTwo.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnTwoActionPerformed(evt);
            }
        });

        btnThree.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnThree.setText("3");
        btnThree.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnThreeActionPerformed(evt);
            }
        });

        btnPlus.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnPlus.setText("+");
        btnPlus.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnPlusActionPerformed(evt);
            }
        });

        btnFour.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnFour.setText("4");
        btnFour.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnFourActionPerformed(evt);
            }
        });

        btnFive.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnFive.setText("5");
        btnFive.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnFiveActionPerformed(evt);
            }
        });

        btnSix.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnSix.setText("6");
        btnSix.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnSixActionPerformed(evt);
            }
        });

        btnSubstraction.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnSubstraction.setText("-");
        btnSubstraction.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnSubstractionActionPerformed(evt);
            }
        });

        btnSeven.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnSeven.setText("7");
        btnSeven.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnSevenActionPerformed(evt);
            }
        });

        btnEight.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnEight.setText("8");
        btnEight.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnEightActionPerformed(evt);
            }
        });

        btnNine.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnNine.setText("9");
        btnNine.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnNineActionPerformed(evt);
            }
        });

        btnMultiply.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnMultiply.setText("*");
        btnMultiply.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnMultiplyActionPerformed(evt);
            }
        });

        btnDot.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnDot.setText("C");
        btnDot.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnDotActionPerformed(evt);
            }
        });

        BtnZero.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        BtnZero.setText("0");
        BtnZero.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                BtnZeroActionPerformed(evt);
            }
        });

        btnEqual.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnEqual.setText("=");
        btnEqual.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnEqualActionPerformed(evt);
            }
        });

        btnDiv.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
        btnDiv.setText("/");
        btnDiv.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnDivActionPerformed(evt);
            }
        });

        javax.swing.GroupLayout jPanel2Layout = new javax.swing.GroupLayout(jPanel2);
        jPanel2.setLayout(jPanel2Layout);
        jPanel2Layout.setHorizontalGroup(
                jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addGroup(jPanel2Layout.createSequentialGroup()
                                .addContainerGap()
                                .addGroup(jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                                        .addGroup(jPanel2Layout.createSequentialGroup()
                                                .addComponent(btnOne, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnTwo, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnThree, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnPlus, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE))
                                        .addGroup(jPanel2Layout.createSequentialGroup()
                                                .addComponent(btnFour, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnFive, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnSix, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnSubstraction, javax.swing.GroupLayout.PREFERRED_SIZE,
                                                        60, javax.swing.GroupLayout.PREFERRED_SIZE))
                                        .addGroup(jPanel2Layout.createSequentialGroup()
                                                .addComponent(btnSeven, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnEight, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnNine, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnMultiply, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE))
                                        .addGroup(jPanel2Layout.createSequentialGroup()
                                                .addComponent(btnDot, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(BtnZero, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnEqual, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)
                                                .addGap(18, 18, 18)
                                                .addComponent(btnDiv, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                        javax.swing.GroupLayout.PREFERRED_SIZE)))
                                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)));
        jPanel2Layout.setVerticalGroup(
                jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addGroup(jPanel2Layout.createSequentialGroup()
                                .addContainerGap()
                                .addGroup(jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                                        .addComponent(btnOne, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnTwo, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnThree, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnPlus, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE))
                                .addGap(18, 18, 18)
                                .addGroup(jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                                        .addComponent(btnFour, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnFive, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnSix, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnSubstraction, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE))
                                .addGap(18, 18, 18)
                                .addGroup(jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                                        .addComponent(btnSeven, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnEight, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnNine, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnMultiply, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE))
                                .addGap(18, 18, 18)
                                .addGroup(jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                                        .addComponent(btnDot, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(BtnZero, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnEqual, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE)
                                        .addComponent(btnDiv, javax.swing.GroupLayout.PREFERRED_SIZE, 60,
                                                javax.swing.GroupLayout.PREFERRED_SIZE))
                                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)));

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addComponent(jPanel2, javax.swing.GroupLayout.DEFAULT_SIZE,
                                javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                        .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE,
                                javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE));
        layout.setVerticalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addGroup(layout.createSequentialGroup()
                                .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE,
                                        javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                                .addComponent(jPanel2, javax.swing.GroupLayout.PREFERRED_SIZE,
                                        javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)));

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

    private void btnOneActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnOneActionPerformed
        if (txtDisplay.getText().equals("0")) {
            txtDisplay.setText("1");
        } else if (pressedSymbol) {
            txtDisplay.setText("1");
            pressedSymbol = false;
        } else {
            String previousValue = txtDisplay.getText();
            txtDisplay.setText(previousValue + "1");
        }

    }// GEN-LAST:event_btnOneActionPerformed

    private void btnTwoActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnTwoActionPerformed
        if (txtDisplay.getText().equals("0")) {
            txtDisplay.setText("2");
        } else if (pressedSymbol) {
            txtDisplay.setText("2");
            pressedSymbol = false;
        } else {
            String previousValue = txtDisplay.getText();
            txtDisplay.setText(previousValue + "2");
        }
    }// GEN-LAST:event_btnTwoActionPerformed

    private void btnThreeActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnThreeActionPerformed
        if (txtDisplay.getText().equals("0")) {
            txtDisplay.setText("3");
        } else if (pressedSymbol) {
            txtDisplay.setText("3");
            pressedSymbol = false;
        } else {
            String previousValue = txtDisplay.getText();
            txtDisplay.setText(previousValue + "3");
        }
    }// GEN-LAST:event_btnThreeActionPerformed

    private void btnPlusActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnPlusActionPerformed
        String previousValues = txtDisplay.getText();
        previousvalue = Integer.parseInt(previousValues);
        pressedAdd = true;
        pressedSymbol = true;
    }// GEN-LAST:event_btnPlusActionPerformed

    private void btnEqualActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnEqualActionPerformed
        String currentValue = txtDisplay.getText();
        int currentVal = Integer.parseInt(currentValue);
        int totalSum = 0;
        if (pressedAdd) {
            totalSum = previousvalue + currentVal;
            pressedAdd = false;
        } else if (pressedSub) {
            totalSum = previousvalue - currentVal;
            pressedSub = false;
        } else if (pressedMul) {
            totalSum = previousvalue * currentVal;
            pressedMul = false;
        } else if (pressedDiv) {
            totalSum = previousvalue / currentVal;
            pressedDiv = false;
        }

        txtDisplay.setText("" + totalSum);
    }// GEN-LAST:event_btnEqualActionPerformed

    private void btnSubstractionActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnSubstractionActionPerformed
        String previousValues = txtDisplay.getText();
        previousvalue = Integer.parseInt(previousValues);
        pressedSub = true;
        pressedSymbol = true;
    }// GEN-LAST:event_btnSubstractionActionPerformed

    private void btnMultiplyActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnMultiplyActionPerformed
        String previousValues = txtDisplay.getText();
        previousvalue = Integer.parseInt(previousValues);
        pressedMul = true;
        pressedSymbol = true;
    }// GEN-LAST:event_btnMultiplyActionPerformed

    private void btnDivActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnDivActionPerformed
        String previousValues = txtDisplay.getText();
        previousvalue = Integer.parseInt(previousValues);
        pressedDiv = true;
        pressedSymbol = true;
    }// GEN-LAST:event_btnDivActionPerformed

    private void btnFourActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnFourActionPerformed
        if (txtDisplay.getText().equals("0")) {
            txtDisplay.setText("4");
        } else if (pressedSymbol) {
            txtDisplay.setText("4");
            pressedSymbol = false;
        } else {
            String previousValue = txtDisplay.getText();
            txtDisplay.setText(previousValue + "4");
        }
    }// GEN-LAST:event_btnFourActionPerformed

    private void btnFiveActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnFiveActionPerformed
        if (txtDisplay.getText().equals("0")) {
            txtDisplay.setText("5");
        } else if (pressedSymbol) {
            txtDisplay.setText("5");
            pressedSymbol = false;
        } else {
            String previousValue = txtDisplay.getText();
            txtDisplay.setText(previousValue + "5");
        }
    }// GEN-LAST:event_btnFiveActionPerformed

    private void btnSixActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnSixActionPerformed
        if (txtDisplay.getText().equals("0")) {
            txtDisplay.setText("6");
        } else if (pressedSymbol) {
            txtDisplay.setText("6");
            pressedSymbol = false;
        } else {
            String previousValue = txtDisplay.getText();
            txtDisplay.setText(previousValue + "6");
        }
    }// GEN-LAST:event_btnSixActionPerformed

    private void btnSevenActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnSevenActionPerformed
        if (txtDisplay.getText().equals("0")) {
            txtDisplay.setText("7");
        } else if (pressedSymbol) {
            txtDisplay.setText("7");
            pressedSymbol = false;
        } else {
            String previousValue = txtDisplay.getText();
            txtDisplay.setText(previousValue + "7");
        }
    }// GEN-LAST:event_btnSevenActionPerformed

    private void btnEightActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnEightActionPerformed
        if (txtDisplay.getText().equals("0")) {
            txtDisplay.setText("8");
        } else if (pressedSymbol) {
            txtDisplay.setText("8");
            pressedSymbol = false;
        } else {
            String previousValue = txtDisplay.getText();
            txtDisplay.setText(previousValue + "8");
        }
    }// GEN-LAST:event_btnEightActionPerformed

    private void btnNineActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnNineActionPerformed
        if (txtDisplay.getText().equals("0")) {
            txtDisplay.setText("9");
        } else if (pressedSymbol) {
            txtDisplay.setText("9");
            pressedSymbol = false;
        } else {
            String previousValue = txtDisplay.getText();
            txtDisplay.setText(previousValue + "9");
        }
    }// GEN-LAST:event_btnNineActionPerformed

    private void BtnZeroActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_BtnZeroActionPerformed
        if (txtDisplay.getText().equals("0")) {
            txtDisplay.setText("0");
        } else if (pressedSymbol) {
            txtDisplay.setText("0");
            pressedSymbol = false;
        } else {
            String previousValue = txtDisplay.getText();
            txtDisplay.setText(previousValue + "0");
        }
    }// GEN-LAST:event_BtnZeroActionPerformed

    private void btnDotActionPerformed(java.awt.event.ActionEvent evt) {// GEN-FIRST:event_btnDotActionPerformed
        txtDisplay.setText("0");
        boolean pressedAdd = false;
        boolean pressedSub = false;
        boolean pressedMul = false;
        boolean pressedDiv = false;
        int previousvalue = 0;
        boolean pressedSymbol = false;
    }// GEN-LAST:event_btnDotActionPerformed

    /**
     * @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(Calculator.class.getName()).log(java.util.logging.Level.SEVERE, null,
                    ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(Calculator.class.getName()).log(java.util.logging.Level.SEVERE, null,
                    ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(Calculator.class.getName()).log(java.util.logging.Level.SEVERE, null,
                    ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(Calculator.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 Calculator().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify//GEN-BEGIN:variables
    private javax.swing.JButton BtnZero;
    private javax.swing.JButton btnDiv;
    private javax.swing.JButton btnDot;
    private javax.swing.JButton btnEight;
    private javax.swing.JButton btnEqual;
    private javax.swing.JButton btnFive;
    private javax.swing.JButton btnFour;
    private javax.swing.JButton btnMultiply;
    private javax.swing.JButton btnNine;
    private javax.swing.JButton btnOne;
    private javax.swing.JButton btnPlus;
    private javax.swing.JButton btnSeven;
    private javax.swing.JButton btnSix;
    private javax.swing.JButton btnSubstraction;
    private javax.swing.JButton btnThree;
    private javax.swing.JButton btnTwo;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JPanel jPanel2;
    private javax.swing.JTextField txtDisplay;
    // End of variables declaration//GEN-END:variables
}