Help accumulating test scores. data enters once but doesn't accumulate.

[OBsolete]

I have the code working to an extent. I can enter the first test score and all the calculations run, but if I try to enter another test score and hit enter score button, I get no result. Any advice?
package StudentScoresFrame;

*/
public class StudentScoresFrame extends javax.swing.JFrame {

/**
* Creates new form StudentScoresFrame
*/
public StudentScoresFrame() {
initComponents();
}
// declare variables
double average = 0.0;
double best = 0.0;
double scores = 0.0;
double sum = 0.0;
double count = 0.0;


private static double scoreCount(double scores)
{
int count = 0;
double num = 0.0;
for(int i = 0; i <= num; i++)
{
count += 1;
}
return count;
} // end
private static double calculateAverage(double scores, double count)
{

double average = 0.0;
double sum = 0.0;

for(int i = 1; i <= count; i++)
{
sum += scores;
average = sum / count;
}
return average;

} // end
private static double bestScore(double scores)
{
int best = 0;
for(int i = 0; i < scores; i++){
if(best >= scores)
{
best = (int) scores;
}
}
return best;
} // end
/**
* 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() {

testScoreLabel = new javax.swing.JLabel();
numScoresLabel = new javax.swing.JLabel();
averageScoreLabel = new javax.swing.JLabel();
bestScoreLabel = new javax.swing.JLabel();
testScoreTextField = new javax.swing.JTextField();
numScoresTextField = new javax.swing.JTextField();
averageScoreTextField = new javax.swing.JTextField();
bestScoreTextField = new javax.swing.JTextField();
enterButton = new javax.swing.JButton();
clearButton = new javax.swing.JButton();
exitButton = new javax.swing.JButton();

setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

testScoreLabel.setText("Test Score:");

numScoresLabel.setText("Number of Scores:");

averageScoreLabel.setText("Average Score:");

bestScoreLabel.setText("Best Score:");

numScoresTextField.setEditable(false);
numScoresTextField.setEnabled(false);
numScoresTextField.setFocusable(false);

averageScoreTextField.setEditable(false);
averageScoreTextField.setEnabled(false);
averageScoreTextField.setFocusable(false);
averageScoreTextField.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
averageScoreTextFieldActionPerformed(evt);
}
});

bestScoreTextField.setEditable(false);
bestScoreTextField.setEnabled(false);
bestScoreTextField.setFocusable(false);

enterButton.setText("Enter Score");
enterButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
enterButtonActionPerformed(evt);
}
});

clearButton.setText("Clear");
clearButton.setToolTipText("");
clearButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
clearButtonActionPerformed(evt);
}
});

exitButton.setText("Exit");
exitButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
exitButtonActionPerformed(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()
.addContainerGap()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
.addComponent(enterButton)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(numScoresLabel)
.addComponent(averageScoreLabel)
.addComponent(bestScoreLabel)
.addComponent(testScoreLabel)))
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(testScoreTextField, javax.swing.GroupLayout.PREFERRED_SIZE, 93, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(averageScoreTextField, javax.swing.GroupLayout.DEFAULT_SIZE, 93, Short.MAX_VALUE)
.addComponent(bestScoreTextField))
.addGroup(layout.createSequentialGroup()
.addComponent(clearButton)
.addGap(18, 18, 18)
.addComponent(exitButton))
.addComponent(numScoresTextField, javax.swing.GroupLayout.PREFERRED_SIZE, 93, javax.swing.GroupLayout.PREFERRED_SIZE))
.addContainerGap(128, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(29, 29, 29)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(testScoreLabel)
.addComponent(testScoreTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(numScoresLabel)
.addComponent(numScoresTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(averageScoreLabel)
.addComponent(averageScoreTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(bestScoreLabel)
.addComponent(bestScoreTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(enterButton)
.addComponent(clearButton)
.addComponent(exitButton))
.addContainerGap(86, Short.MAX_VALUE))
);

pack();
}// </editor-fold>

private void exitButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
System.exit(0);
}

private void averageScoreTextFieldActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}

private void enterButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:

if (isValidData())
{
scores = Double.parseDouble(testScoreTextField.getText());


count = scoreCount(scores);

average = calculateAverage(scores, count);

numScoresTextField.setText("" + count);
averageScoreTextField.setText("" + average);

best = bestScore(scores);
bestScoreTextField.setText("" + best);

} // end


}
private boolean isValidData()
{
SwingValidator sv = new SwingValidator();
return
sv.isPresent(testScoreTextField,
"Test Score") &&
sv.isDouble(testScoreTextField,
"Test Score");
} // end
private void clearButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:T
testScoreTextField.setText("");
numScoresTextField.setText("");
averageScoreTextField.setText("");
bestScoreTextField.setText("");

}

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

// Variables declaration - do not modify
private javax.swing.JLabel averageScoreLabel;
private javax.swing.JTextField averageScoreTextField;
private javax.swing.JLabel bestScoreLabel;
private javax.swing.JTextField bestScoreTextField;
private javax.swing.JButton clearButton;
private javax.swing.JButton enterButton;
private javax.swing.JButton exitButton;
private javax.swing.JLabel numScoresLabel;
private javax.swing.JTextField numScoresTextField;
private javax.swing.JLabel testScoreLabel;
private javax.swing.JTextField testScoreTextField;
// End of variables declaration
}

[Norm]

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