Java calculator problem ???

[danielmessick]

Hello, I'm trying to fix my Java applet to have a fully functional calculator. I managed to create the buttons and have the +, -, /, *, =, and clear buttons WORKING. But, I cant seem to figure out how to get the decimal(.), squareroot, percent(%), reciprocal(1/x), and -/+ buttons working.. Can anyone help??

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
 
/*
 * JavaCalculator.java
 *
 * Created on Mar 12, 2010, 2:59:41 PM
 */
 
package jCalculator;
 
/**
 *
 * @author Owner
 */
public class JavaCalculator extends javax.swing.JFrame {
 
    private double total1 = 0.0;
    private double total2 = 0.0;
    private char math_operator;
    /** Creates new form JavaCalculator */
    public JavaCalculator() {
        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">
    private void initComponents() {
 
        jPanel1 = new javax.swing.JPanel();
        btnSeven = new javax.swing.JButton();
        btnEight = new javax.swing.JButton();
        btnNine = new javax.swing.JButton();
        btnFour = new javax.swing.JButton();
        btnOne = new javax.swing.JButton();
        btnFive = new javax.swing.JButton();
        btnSix = new javax.swing.JButton();
        btnTwo = new javax.swing.JButton();
        btnThree = new javax.swing.JButton();
        btnZero = new javax.swing.JButton();
        btnDivide = new javax.swing.JButton();
        btnSquareroot = new javax.swing.JButton();
        btnMultiply = new javax.swing.JButton();
        btnPercentage = new javax.swing.JButton();
        btnMinus = new javax.swing.JButton();
        btnReciprocal = new javax.swing.JButton();
        btnPlus = new javax.swing.JButton();
        btnEquals = new javax.swing.JButton();
        btnZero1 = new javax.swing.JButton();
        btnZero2 = new javax.swing.JButton();
        txtDisplay = new javax.swing.JTextField();
        btnClear = new javax.swing.JButton();
 
        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("Calculator");
 
        btnSeven.setFont(new java.awt.Font("Arial", 1, 12)); // NOI18N
        btnSeven.setForeground(new java.awt.Color(0, 153, 153));
        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("Arial", 1, 12)); // NOI18N
        btnEight.setForeground(new java.awt.Color(0, 153, 153));
        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("Arial", 1, 12)); // NOI18N
        btnNine.setForeground(new java.awt.Color(0, 153, 153));
        btnNine.setText("9");
        btnNine.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnNineActionPerformed(evt);
            }
        });
 
        btnFour.setFont(new java.awt.Font("Arial", 1, 12)); // NOI18N
        btnFour.setForeground(new java.awt.Color(0, 153, 153));
        btnFour.setText("4");
        btnFour.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnFourActionPerformed(evt);
            }
        });
 
        btnOne.setFont(new java.awt.Font("Arial", 1, 12)); // NOI18N
        btnOne.setForeground(new java.awt.Color(0, 153, 153));
        btnOne.setText("1");
        btnOne.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnOneActionPerformed(evt);
            }
        });
 
        btnFive.setFont(new java.awt.Font("Arial", 1, 12)); // NOI18N
        btnFive.setForeground(new java.awt.Color(0, 153, 153));
        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("Arial", 1, 12)); // NOI18N
        btnSix.setForeground(new java.awt.Color(0, 153, 153));
        btnSix.setText("6");
        btnSix.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnSixActionPerformed(evt);
            }
        });
 
        btnTwo.setFont(new java.awt.Font("Arial", 1, 12)); // NOI18N
        btnTwo.setForeground(new java.awt.Color(0, 153, 153));
        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("Arial", 1, 12)); // NOI18N
        btnThree.setForeground(new java.awt.Color(0, 153, 153));
        btnThree.setText("3");
        btnThree.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnThreeActionPerformed(evt);
            }
        });
 
        btnZero.setFont(new java.awt.Font("Arial", 1, 12)); // NOI18N
        btnZero.setForeground(new java.awt.Color(0, 153, 153));
        btnZero.setText("0");
        btnZero.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnZeroActionPerformed(evt);
            }
        });
 
        btnDivide.setFont(new java.awt.Font("Arial", 1, 18)); // NOI18N
        btnDivide.setForeground(new java.awt.Color(204, 0, 0));
        btnDivide.setText("/");
        btnDivide.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnDivideActionPerformed(evt);
            }
        });
 
        btnSquareroot.setFont(new java.awt.Font("Arial", 0, 10)); // NOI18N
        btnSquareroot.setForeground(new java.awt.Color(0, 153, 153));
        btnSquareroot.setText("sqrt");
        btnSquareroot.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnSquarerootActionPerformed(evt);
            }
        });
 
        btnMultiply.setFont(new java.awt.Font("Arial", 1, 18)); // NOI18N
        btnMultiply.setForeground(new java.awt.Color(204, 0, 0));
        btnMultiply.setText("*");
        btnMultiply.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnMultiplyActionPerformed(evt);
            }
        });
 
        btnPercentage.setFont(new java.awt.Font("Arial", 1, 14)); // NOI18N
        btnPercentage.setForeground(new java.awt.Color(0, 153, 153));
        btnPercentage.setText("%");
 
        btnMinus.setFont(new java.awt.Font("Arial", 1, 14)); // NOI18N
        btnMinus.setForeground(new java.awt.Color(204, 0, 0));
        btnMinus.setText("-");
        btnMinus.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnMinusActionPerformed(evt);
            }
        });
 
        btnReciprocal.setFont(new java.awt.Font("Arial", 1, 11)); // NOI18N
        btnReciprocal.setForeground(new java.awt.Color(0, 153, 153));
        btnReciprocal.setText("1/x");
        btnReciprocal.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnReciprocalActionPerformed(evt);
            }
        });
 
        btnPlus.setFont(new java.awt.Font("Arial", 1, 14)); // NOI18N
        btnPlus.setForeground(new java.awt.Color(204, 0, 0));
        btnPlus.setText("+");
        btnPlus.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnPlusActionPerformed(evt);
            }
        });
 
        btnEquals.setFont(new java.awt.Font("Arial", 1, 14)); // NOI18N
        btnEquals.setForeground(new java.awt.Color(204, 0, 0));
        btnEquals.setText("=");
        btnEquals.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnEqualsActionPerformed(evt);
            }
        });
 
        btnZero1.setFont(new java.awt.Font("Arial", 1, 12)); // NOI18N
        btnZero1.setForeground(new java.awt.Color(0, 153, 153));
        btnZero1.setText("-/+");
        btnZero1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnZero1ActionPerformed(evt);
            }
        });
 
        btnZero2.setFont(new java.awt.Font("Arial", 1, 18)); // NOI18N
        btnZero2.setForeground(new java.awt.Color(0, 153, 153));
        btnZero2.setText(".");
        btnZero2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnZero2ActionPerformed(evt);
            }
        });
 
        javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addComponent(btnSeven, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(btnEight, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(btnNine, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(btnDivide, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(btnSquareroot, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addComponent(btnFour, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(btnFive, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(btnSix, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(btnMultiply, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(btnPercentage, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addComponent(btnOne, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(btnTwo, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addComponent(btnZero, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(btnZero1, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                    .addComponent(btnThree, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnZero2, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addComponent(btnPlus, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(btnEquals, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
                    .addGroup(jPanel1Layout.createSequentialGroup()
                        .addComponent(btnMinus, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                        .addComponent(btnReciprocal, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))))
        );
        jPanel1Layout.setVerticalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                        .addComponent(btnSeven, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(btnEight, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(btnNine, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(btnDivide, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
                    .addComponent(btnSquareroot, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                        .addComponent(btnFour, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(btnFive, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(btnSix, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(btnMultiply, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
                    .addComponent(btnPercentage, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(btnOne, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnTwo, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnThree, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnMinus, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnReciprocal, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(btnZero, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnPlus, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnEquals, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnZero1, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(btnZero2, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addContainerGap())
        );
 
        txtDisplay.setEditable(false);
        txtDisplay.setFont(new java.awt.Font("Arial", 0, 14)); // NOI18N
 
        btnClear.setFont(new java.awt.Font("Arial", 1, 14)); // NOI18N
        btnClear.setForeground(new java.awt.Color(204, 0, 0));
        btnClear.setText("C");
        btnClear.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnClearActionPerformed(evt);
            }
        });
 
        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(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                        .addContainerGap(176, Short.MAX_VALUE)
                        .addComponent(btnClear, javax.swing.GroupLayout.PREFERRED_SIZE, 108, javax.swing.GroupLayout.PREFERRED_SIZE))
                    .addGroup(layout.createSequentialGroup()
                        .addContainerGap()
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(txtDisplay, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, 274, Short.MAX_VALUE)
                            .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))))
                .addContainerGap())
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(txtDisplay, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(btnClear, javax.swing.GroupLayout.PREFERRED_SIZE, 45, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
        );
 
        pack();
    }// </editor-fold>
 
    private void getOperator(String btnText) {
        math_operator = btnText.charAt(0);
        total1 = total1 + Double.parseDouble(txtDisplay.getText());
        txtDisplay.setText("");
    }
 
 
    private void btnOneActionPerformed(java.awt.event.ActionEvent evt) {
    String btnOneText = txtDisplay.getText() + btnOne.getText();
    txtDisplay.setText(btnOneText);
    }
 
    private void btnTwoActionPerformed(java.awt.event.ActionEvent evt) {
    String btnTwoText = txtDisplay.getText() + btnTwo.getText();
    txtDisplay.setText(btnTwoText);
    }
 
    private void btnThreeActionPerformed(java.awt.event.ActionEvent evt) {
    String btnThreeText = txtDisplay.getText() + btnThree.getText();
    txtDisplay.setText(btnThreeText);
    }
 
    private void btnFourActionPerformed(java.awt.event.ActionEvent evt) {
    String btnFourText = txtDisplay.getText() + btnFour.getText();
    txtDisplay.setText(btnFourText);
    }
 
    private void btnFiveActionPerformed(java.awt.event.ActionEvent evt) {
    String btnFiveText = txtDisplay.getText() + btnFive.getText();
    txtDisplay.setText(btnFiveText);
    }
 
    private void btnSixActionPerformed(java.awt.event.ActionEvent evt) {
    String btnSixText = txtDisplay.getText() + btnSix.getText();
    txtDisplay.setText(btnSixText);
    }
 
    private void btnSevenActionPerformed(java.awt.event.ActionEvent evt) {
    String btnSevenText = txtDisplay.getText() + btnSeven.getText();
    txtDisplay.setText(btnSevenText);
    }
 
    private void btnEightActionPerformed(java.awt.event.ActionEvent evt) {
    String btnEightText = txtDisplay.getText() + btnEight.getText();
    txtDisplay.setText(btnEightText);
    }
 
    private void btnNineActionPerformed(java.awt.event.ActionEvent evt) {
    String btnNineText = txtDisplay.getText() + btnNine.getText();
    txtDisplay.setText(btnNineText);
    }
 
    private void btnZeroActionPerformed(java.awt.event.ActionEvent evt) {
    String btnZeroText = txtDisplay.getText() + btnZero.getText();
    txtDisplay.setText(btnZeroText);
    }
 
    private void btnClearActionPerformed(java.awt.event.ActionEvent evt) {
    total2 = 0;
txtDisplay.setText("");
    }
 
    private void btnEqualsActionPerformed(java.awt.event.ActionEvent evt) {
 
        switch ( math_operator ) {
            case '+':
                total2 = total1 + Double.parseDouble( txtDisplay.getText( ) ) ;
                break;
            case '-':
                total2 = total1 - Double.parseDouble(txtDisplay.getText( ) );
                break;
            case '/':
                total2 = total1 / Double.parseDouble(txtDisplay.getText( ) );
                break;
            case '*':
                total2 = total1 * Double.parseDouble(txtDisplay.getText( ) );
                break;
 
        }
 
        txtDisplay.setText( Double.toString(total2) );
        total1 = 0;    // TODO add your handling code here:
}
 
    private void btnPlusActionPerformed(java.awt.event.ActionEvent evt) {
        String button_text = btnPlus.getText();
        getOperator(button_text);
}
 
    private void btnMinusActionPerformed(java.awt.event.ActionEvent evt) {
        String button_text = btnMinus.getText();
        getOperator(button_text);
}
 
    private void btnMultiplyActionPerformed(java.awt.event.ActionEvent evt) {
        String button_text = btnMultiply.getText();
        getOperator(button_text);
}
 
    private void btnDivideActionPerformed(java.awt.event.ActionEvent evt) {
        String button_text = btnDivide.getText();
        getOperator(button_text);
}
 
    private void btnReciprocalActionPerformed(java.awt.event.ActionEvent evt) {
 
    float num,result;
    num=Float.parseFloat(btnReciprocal.getText());
    result = 1/num;
    btnReciprocal.setText(String.valueOf(result));
 
    }
 
    private void btnSquarerootActionPerformed(java.awt.event.ActionEvent evt) {
        float num,result;
 
    num=Float.parseFloat(btnSquareroot.getText());
    result=num*num;
    btnSquareroot.setText(String.valueOf(result));
    }
 
    private void btnZero1ActionPerformed(java.awt.event.ActionEvent evt) {
        // TODO add your handling code here:
    }
 
    private void btnZero2ActionPerformed(java.awt.event.ActionEvent evt) {
        // TODO add your handling code here:
    }
 
    /**
    * @param args the command line arguments
    */
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new JavaCalculator().setVisible(true);
            }
        });
    }
 
    // Variables declaration - do not modify
    private javax.swing.JButton btnClear;
    private javax.swing.JButton btnDivide;
    private javax.swing.JButton btnEight;
    private javax.swing.JButton btnEquals;
    private javax.swing.JButton btnFive;
    private javax.swing.JButton btnFour;
    private javax.swing.JButton btnMinus;
    private javax.swing.JButton btnMultiply;
    private javax.swing.JButton btnNine;
    private javax.swing.JButton btnOne;
    private javax.swing.JButton btnPercentage;
    private javax.swing.JButton btnPlus;
    private javax.swing.JButton btnReciprocal;
    private javax.swing.JButton btnSeven;
    private javax.swing.JButton btnSix;
    private javax.swing.JButton btnSquareroot;
    private javax.swing.JButton btnThree;
    private javax.swing.JButton btnTwo;
    private javax.swing.JButton btnZero;
    private javax.swing.JButton btnZero1;
    private javax.swing.JButton btnZero2;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JTextField txtDisplay;
    // End of variables declaration
 
}
 
 

[jkmyoung]

Instead of btnReciprocal.g etText() you need to be getting the text from the display, eg, txtDisplay.getT ext()
It's pretty much a global replace to only get the text from the display, and only set the text to the display, not the buttons themselves.